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Service Manual FV4

1. RED 24 Fig 34 Typical HK61GA001 View 10kw to 20kw Circuits A8 BLU Q 0 BLK ye L imd SS INDOOR 9 EI THERMOSTAT Y H 2FC 1 Ih CONNECT E TOE Sv CO aeina LL gt lt 9 lt eo i CD 502 gt O ORG GRAY e 61 699 AUX1 BRN O 6 5 4 24VDC YEL AA 9 7 gt 29 ler BLU RELAY TRANSFORMER BLK HI AC LINE DUMMY po _ REDLO Ti T3 L2 EAC2 DUMMY COMMON DUMMY FAN FI L1 EAC1 COMMON CAP 240 240 YEL COM GRNYELGND 208V RED COMM 230V TRAN 24V A97027 a Thermostat and Relay Control When the thermostat calls for the fan in cooling heat pump electric heat fan only mode 24 v de signal is sent to the relay This causes the relay to close its normally open contacts thus turning on the fan When the thermostat no longer calls for the fan the signal sent to the relay is turned off and the relay opens causing the fan to turn off The HK61GA003 board contains a 90 sec fan off delay when Y is de energized a Sequencer
2. A94079 Fig 3 FK4B FK4C and FV4A motor Motor LOW VOLTAGE TERMINAL BLOCK EASY SELECT 5 AMP AUX HEAT RANGE 03 j o2 02 05 1200 1000 800 600 S HY AC HP SIZE 4 042 036 030 024 CIRCUIT CEOE E BOARD AC HP COMFORT HP EFF R1 0 30 2 JUMPER MOLEX 7 PIN 4 7 3RD STAGE 1 MOTOR wee 50000001 W2 W3 JUMPER ee 2ND STAGE SCREW SEC2 a 1 REQUIRED Dm a T 69 2AVAC 1 ERIT DE 46 IN MALE n FASTON FASTON c 02 109 21 PLCS OO OC ger sinis 1 08107105 106 CES0130007 00 AMP 12 PIN MATE N LOCK CONNECTOR 1 A94076 Fig 4 Easy Select Board FK4B Connection to heater panel is made through 12 circuit connector P1 Connections to thermostat are made at screw terminals Line voltage for motor is made through 12 circuit connector P1 Eighteen quick connect terminals comprise field select taps for motor SH 4
3. YEL SEQ2 BLK 183 BLK 5 BLK YEL 152 HTR2 BLK BLK EQ 1 YEL LS1 HTR1 BLK SEM BLK lt 2 YEL P BLU BLK TERM BOARD 3j E gt lt L gt X 2 Y R G RED OBRN YEL BLK BLU AC LINE EAC2 T2 1 1 240 240 YEL COMMON BLK BLU RED COMM 208V 230V ON TERMINAL BOARD ABOVE Fig 39 Wiring Schematic HK61GA001 54 INDOOR THERMOSTAT A97032 2 Check the output voltage of the secondary side R and of the transformer If the circuit board is HK61GA003 make sure the ground strap is in place from C to the bracket This strap must be in place to complete the 24 v circuit Make sure the transformer output is around 24 vac If the transformer output is zero vac and the transformer is receiving the correct input voltage 208 240 then the transformer needs to be replaced with the recommended transformer If the transformer output is 24 vac then proceed to 3 and 4 3 Check the low voltage fuse shown in Fig 32 and Fig 33 If the fuse is blown replace it The transformer cannot supply power to the board with the fuse blown or loose If the fuse blow
4. 13 EO 60 2 RED LOW CAP GND YELCOM FAN MOTOR THERMALLY PROTECTED Fa RED z BLU MED TRAN LED FLASH CODES CL NO LIGHT OR FLASH YEL COM BRN j 1 BOARD FAILURE GRN YEL GND NOTES STEADY LIGHT BOARD FAILURE 1 USE COPPER WIRE 75 C MIN ONLY BETWEEN INDOOR THERMOSTAT DISCONNECT SWITCH AND UNIT SEE NOTES 2 7 AND 8 STEADY FLASH STAND BY CONDITION 2 CONNECT LOW VOLTAGE WIRING AS SHOWN 24VAC LEGEND OR FAN ONLY 3 CONNECT TRANSFORMER PRIMARY TO THE PROPER ee 1 FLASH HEAT PUMP HEAT VOLTAGE TERMINAL DIAGNOSTIC LIGHT 4 TO BE WIRED IN ACCORDANCE WITH NEC AND LOCAL CODES pm 2 FLASHES HEAT PUMP PLUS 5 IF ANY OF THE ORIGINAL WIRE AS SUPPLIED MUST BE LOWNOLTF SE LVTB LOW VOLT TERM BRD 1 SEQUENCER REPLACED USE THE SAME OR EQUIVALENT TYPE WIRE SEQ SEQUENCER 3 FLASHES HEAT PUMP PLUS 6 REPLACE LOW VOLTAGE FUSE WITH NO GREATER THAN FW 2 SEQUENCERS TRAN TRANSFORMER GND EQUIPMENT GROUND HEAT PUMP PLUS PCB TRAN TERMINALS 4 FLASHES 7 REFER TO THERMOSTAT INSTRUCTIONS FOR JUMPER HPLV LOW VOLT SEQUENCERS INSTALLATION HTR 5 FLASHES COO
5. 0 MOTOR f 219 GND RECP 3 t BLK BLU LABEL 2 USE COPPER WIRE 75 C MIN ONLY BETWEEN DISCONNECT SWITCH AND UNIT TO BE WIRED IN ACCORDANCE WITH NEC AND LOCAL CODES TRANSFORMER PRIMARY LEADS BLUE 208V RED 230V IF ANY OF THE ORIGINAL WIRE AS SUPPLIED MUST BE REPLACED USE THE SAME OR EQUIVALENT TYPE WIRE REPLACE LOW VOLTAGE FUSE WITH NO GREATER THAN 5 AMP FUSE DUAL CIRCUIT WIRING SHOWN USE 60 AMP CLASS K FUSES ONLY FOR REPLACEMENT CONNECT GTO ETC SEE OUTDOOR INSTRUCTION FOR DETAILS SEE INSTRUCTION FOR INSTALLATION 325653 101 REV B 13 FKAC FV4A and 40FKA Wiring Diagram with 20kw heater after heater serial 1900A56372 18 00178 Turn power back and check the following 3 Check for 24vac on 5 and SEC2 If no voltage is present check transformer 4 Verify that approximately 230vac is present at motor 5 Verify low voltage control signals to motor according to procedure below Use following procedure to chec
6. 9 4 paseoun ul peun4 3 43 pase ul pany suo MNN 200 09 1 062 S exnjeq 9 suo 100 09 1 062 802 piepuels uo 720 09 1 911 seueg puooes V 1 810 ueJ uotiisog v 9215 Buljoo5 sole soyioads v senes 4 asiodninw puepuels v ue uonisod 19 ue 4 yo 1 91 SI L ci EE OL 682 9 9 DO NOT REMOVE OPTIONAL SAFETY GROUND 2909 POWER CONNECTOR Cepto riria iss o 1121134150617 8 CONTROL CONNECTOR OPTIONAL SAFETY GROUND v IN ee d HOLE
7. FF1A FF1B FF1C CONTROL BOX A98184 Fig 20 Electric Heater Control Boxes B Sequencer Refer to Electric Heater Function and Troubleshooting section of this manual C Transformer A 40 VA transformer supplies 24 v power for control circuit Check for 208 230v on primary side of transformer If present check for 24v on secondary side NOTE Transformer is fused Do not short circuit D Fan Relay Relay coil is 24 volts Check for proper control voltage Replace relay if faulty PROCEDURE 3 CLEANING OR REPLACING REFRIGERANT FLOW CONTROL DEVICE Refer to Fig 27 and instructions given in Piston Body Cleaning or Replacement section above PROCEDURE 4 LIQUID TUBE STRAINER The refrigerant flow control device is protected by a wire mesh strainer It is located inside the 3 8 in liquid tube at field braze joint next to flow control device Access to strainer is through field braze joint PROCEDURE 5 SEQUENCE OF OPERATION Refer to Fig 21 A Condensing Unit COOLING When thermostat calls for cooling the circuit between R and G is complete and single pole single throw relay FR is energized The normally open contacts close causing blower to operate The circuit between R and Y is also complete This completed circuit causes contactor in outdoor unit to close which starts compressor and outdoor fan HEATING When thermostat calls for heating and FAN switch is set on AUTO the circuit between R and W is com
8. H3MOd 1 1810 1 09395 OL OVA 80 Q amp odG av3iaasnNn avaiaasnNun NONINOO 8 39vL 10A lt OWA 41 93345 1 NVA 160 6 pue 1 8 89890 LNALV1 AV T3H 83385 3IALL OVA AVIdG LVLSCINNH LSH LINDYID 89 Aviad Hd H3MOd H3MOd AHOLOVA 1410 TWNIWYAL GAMYVNNO ADVLIOA MOT KOH Ke 43885 H3MO CO OL ON 99600900 Ol avai NOWINOO GdS HIN IH 94 MOT 3545 OL ON S IVNIINH3 L DR cs ed 7 NMOHS IYNOILdO AV LSIGIINQH OL FU4 YEL LS 4 HTR4 BLK BLK rue O O 8
9. Type Type No Description Connection Connector Heater 12 Pin Common to screw terminal G Connection Common to screw terminal Y Y2 through diode D3 Common to Y1 through diode D2 Common to W2 screw terminal Common to W2 screw terminal Common to screw terminal W1 screw terminal Common to W1 screw terminal 24VAC Common to transformer C Common to transformer C Common to transformer C Common to DH screw terminal H Non Staged Auxiliary Heat with Heat Pump Heating Mode Thermostat should already have closed R to G R to Y2 for heat pump heating operation With J2 jumper in place energizing either W1 or W2 will produce the W2 airflow This is the greater of heat pump heating and auxiliary heat airflow plus an additional 15 The elected delay profile 15 not active in this mode l Staged Auxiliary Heat with Heat Pump Heating Mode The auxiliary heat can be staged by removing the J2 jumper that ties W1 and W2 terminals together Staging can be done by using outdoor thermostats or by using the Intelligent Heat Staging option where the indoor control can be configured for 3 stage electric heat The unit will automatically adjust airflow when the different stages of heat are energized The airflow delivered will depend on the heat pump size selected and electric heat size selected The greater of the two airflows will be delivered The selected delay profile is not active in this mode J Electric Heat without Heat Pump Thermo
10. LINDYID 89 84 H3MOd 91915 ONIYIM H3MOd AYOLOVA NVJ Q33dS 1410 97514 IVNIINH3IL WNINYSL Qquvoa ADVLIOA OvAovegoz IAA ve Q 9 9 GdS HLN IH NOWNOONV4 GdSHlW peeds om se Qqv31NONINOO YOLOW X 9 1 03348 YOLOW GaSNNN 303 S IVNIINH3 EL ANNNA 5445 H3H9IH Qqaads OL S IVNIAH3 L 1109 50 1043002 Apoeded 1 9 6c0Z6V 1 89890 1Y1SIdINNH LSH 89 UE cie NIHIM H3MOd 1910 01915 TWNINHAL 7VNIWH3I Qquvoa 39vL 10A 13A ove goz 2866606 H3MO1 EM A OLON Qv31 NOWWOO qva AdS YLW IH HOLON NONINOO 4345 NVA LVLSIGINNH OL 39NVHO OL ON 0 0 6 INIL 89850 0 80 H3MOd 01915
11. 30 0 ENH 90 90 0 a tes CONTINUOUS FAN AUX LO YEL I I AUX2 HUM2 6 5 d PL1 a 1 C HEATER MOTOR GRY A96430 Fig 11 Easy Select Board SYSTEM DIAGRAM HEATER MOTOR SEC1 SEC2 5 B mem i 5 S DH AUX1 C J1 5 S R UN QW AUX2 gt Y i GRY DIODE LOGIC 9 d t ov Y Vo Y AC HP SYSTEM AC HP CFM ON OFF CONTINUOUS KW CFM SIZE TYPE ADJUST DELAY FAN 96431 Fig 12 Easy Select Board Schematic F Heat Pump Heating Mode Single Sp eed or 2 Speed High Thermostat closes R to Y Y2 and R to G A circuit R to Y1 is required for 2 speed high operation The unit delivers airflow selected by AC HP SIZE selection and CFM ADJUST selection Selected delay profile is active in this mode G Heat Pump Heating Mode 2 Speed Low Thermostat closes R to G and R to Y1 Unit delivers 2 speed low airflow for AC HP SIZE and CFM ADJUST selected Selected delay profile is active in this mode ua Table 6 Connections and Connector
12. 2 Check fuse on fan coil control to be sure it is not blown If fuse is open check system wiring before replacing it to be sure a short does not cause a failure of replacement fuse If COMM LED does not light within proper time period and status code is displayed 1 Check system wiring to be sure User Interface is powered and connections are made A to A to B etc and wiring is not shorted Mis wiring or shorting of the ABCD communications wiring will not allow successful communications NOTE Shorting or mis wiring low voltage system wiring will not cause damage to fan coil control or User Interface but may cause low voltage fuse to open OPTIONAL SAFETY GROUND DRAIN HOLE OX AZ 599 POWER CONNECTOR 1519 1121134150617 LET DRAIN HOLE T CONTROL CONNECTOR OPTIONAL SAFETY GROUND m U CONTROL POWER qaoooanp ILLI 000 0000 4 00 00004 7 m DRAIN HOLE A98201 Fig 16 FE4A ECM2 5 Motor C ECM Motor Troubleshooting The ECM motor used in this product consists of two parts the control module and the motor winding section Do not assume motor or module is defective if it will not start Use the designed in LED information aids and follow t
13. 81 HIGH VOLTAGE E03 1 Jw2 gt mo RM O Bos t pu i paul D2 un 5 8 5 1 6 o p E JW 10 12 10 4 1 meget tos S 4 1 1 R3 22 1 ccs 1 1K 2W 57 Mos t aux 1 E 2 x i 4 1 SEC2 Ps1 04 1 1 4 2 ST 4 2 1 1 R2 1 5 D10 lo 1K 2W 7 40 C2 sn So 5 zo 16 vive 2 1 2W sT1 30 20 5 10 0 5 4 1 7 AUX HEAT 1200 1000 800 600 n OW RANGE ac 1 1 042 036 030 024 ROHE acs T Dk HP COM HP EFF T Z i Low MED CFM TRIM T 1 T ON 0 30 30 0 90 90 30 0 BELAY T acis C T acis CI f Fig 5 Easy Select Board Circuitry FK4B Fuse Data 5 amp automotive type ATC ATO tan 32v 200 percent current opening time of 5 sec maximum
14. A Electrical Connections A94077 Eighteen 0 187 in quick connect terminals are used to provide programming selections for operating modes of motor The 5 selection modes are listed below For additional information refer to Easy Select Configuration Taps section AUX Heat Range Violet Wire AC HP Size Blue Wire Type Orange Wire AC HP CFM Adjust Black Wire AC HP Time Delay Grey Wire PROCEDURE 3 SEQUENCE OF OPERATION FK4B A Continuous Fan Mode The thermostat closes circuit R to G The G signal is sent directly to motor B Cooling Mode Single Speed or 2 Speed High Thermostat closes circuits R to Y Y2 and R to O heat pump only for single speed A circuit from R to Y1 is also required for 2 speed high The Y Y2 signal is sent directly to motor C Cooling Mode Two Speed Low Thermostat closes circuits R to Y1 and R to O heat pump only The Y1 signal is sent directly to motor D Electric Heat Heating Mode Thermostat closes circuit R to W2 W3 or E The terminal block positions W2 W3 and E are tied together by jumpers JW1 and JW2 These jumpers are provided for field staging of electric heater banks through use of thermostats When staging is a requirement installer cuts jumpers and wires in thermostats as is the common practice with other fan coils To ensure motor operation if any 1 of the inputs is energized the 3 electric heater inputs are also interlocked through diodes D1 D2 and D3 to mot
15. AUX HEAT KW CFM ele o OUTDOOR UNIT CAUTION NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING ATTENTION NE CONVIENT PAS AUX INSTALLATIONS DE PLUS DE 150 150V TO GROUND VALA TERRE LEGEND COMMON LOW VOLTAGE FUSE FAN MOTOR FIELD POWER WIRING LINE FUSE EQUIPMENT GROUND HIGH VOLT AGE TERM BLOCK HEATER R RECTIFIER LIMIT SWITCH MARKED TERMINAL PLUG AND RECEPTAC LE PRINTED CIRCUIT BOARD TRANSFORMER RECEPTACLE CIRCUIT BREAKER RELAY TIME DELAY RECTIFIER FIELD POWER WIRING COOLING CONTROL ONLY FIELD SYSTEM TRANSFORMER 40 0VA FAN COIL HEATER 8 2VA REMAINING VA AVAILABLE 31 8VA BLK WIRING YEL 9 1 7 4 PLUG 2 208 240VAC 9 T 7 2 CB2 60 60 AC HP SIZE o o SYSTEM TYPE HP COMFORT AC HP ADJUST NOM LO ON OFF DELAY 30 90 0 CONTINUOUS FAN MED HI 1919 1919 INDOOR THERMOSTAT LO 49191166698 SEC1 SEC2
16. FUSE INTERLOCK p 5 LOW VOLTAGE DIODES ST a co Uz PLUG OOo CONNECTIONS 6 6 FOR VARIOUS 900 ACCESSORIES FAN TRANSFORMER RELAY __ CONNECTIONS ME F8 FAN CONNECTIONS F2 T2 12 EAC2 DUMMY COMMON DUMMY FAN Fi Lt 1 COMMON 240 VAC 7 ELECTRONIC AIR CLEANER CONNECTIONS A97025 Fig 32 HK61GA001 Printed Circuit Board 1 The low voltage terminal board is used to connect the indoor thermostat to the low 24 v side of the transformer and to serve as a junction between the indoor thermostat and the outdoor section 2 Break off the tabs a W2 3 Used to control stage the second stage of electric heat The first stage controlling electric heat and the indoor fan are interlocked through diodes b W2 E Used to control stage the third stage of electric heat 3 A fuse is used to protect the low voltage transformer 4 AUX 1 and AUX 2 are connections for the latent capacity control delay off kit 2 speed kit and air conditioning accessories 5 F2 and F4 are connections for the indoor fan 6 and EAC2 are 240 v connections which parallel fan lead connections for the electronic air cleaner 7 11 and L2 are 240 v connections which parallel power input 8 T2 and T3 are connections for the primary high voltage side of the transformer 9 The fan relay is controlled by the thermostat and turns the fan on a
17. volts DC During continuous fan operation with no call for heating or cooling LED indicates a steady flash the same indication seen when system is in standby The call for continuous fan operation signal can be checked by placing voltmeter leads across terminals G and C of control s low voltage terminal strip If 24v is not seen across these terminals check for the following s 24v available across R and C If not refer to Ready To Start section for items to check if 24v is not available s thermostat fan switch set for continuous operation Confirm fan operation Voltage to operate fan can be confirmed by placing voltmeter leads across terminals and HI on control The reading should be 208 230v If 208 230v is not observed check the following s 208 230v available at pins 7 and 9 of 9 pin connector Is connection to board tight e Are line voltage fuses FU1 and FU2 good If 208 230v is available across terminals F1 and and fan does not operate check the following s fan motor capacitor good s blower wheel jammed or loose Are there any other mechanical problems preventing fan operation C Cooling On a call for cooling room thermostat provides input signals to control board at terminals Y and O The O signal is also available to heat pump to energize reversing valve When it receives both these signals the microprocessor responds by providing a 24 v output signal at the terminal This output signal energiz
18. CAUTION UNIT COMPONENT HAZARD Failure to follow this caution could result in equipment damage Use a backup wrench and do not overtighten as deformation of refrigerant flow control device body will occur causing piston to lodge in a partially open or closed position Install new or cleaned piston in refrigerant flow control device body Install new retainer because of probable damage which occurred in initial removal Reconnect refrigerant tube to refrigerant flow control device O Pressurize tubing and coil then leak check 10 Evacuate tubing and coil as necessary PROCEDURE 4 LIQUID TUBE STRAINER The refrigerant flow control device is protected on indoor coil by a wire mesh strainer If strainer becomes plugged 1 Complete items 1 and 2 under Cleaning or Replacing Refrigerant Flow Control Device section Loosen flare fitting joint connecting refrigerant flow control device to coil liquid refrigerant tube Remove sheet metal screw holding bracket clip in place Screw is located between coil and refrigerant flow control device Pull bracket clip out Remove refrigerant flow control device assembly A W N Pull strainer out of coil liquid refrigerant tube and replace with new strainer 34 PROCEDURE 5 CARE AND MAINTENANCE WARNING PERSONAL INJURY HAZARD Failure to follow this caution could result in personal injury Hinged access panel contains electrical components and is
19. MOTOR SPEED TWO LO 10 LO A98229 Fig 19 FF1D Typical Wiring Diagram 7 Slide blower assembly to blower deck Be sure once blower is within the unit casing to force blower assembly toward control box while sliding assembly into unit to ensure that blower assembly engages deck properly 8 Fasten blower assembly to deck with screws previously removed 9 Reconnect electrical leads to PCB 10 Reconnect electrical power to unit and test fan for proper rotation FF1A FF1B FF1C SERVICE AND TROUBLESHOOTING NOTE For FFID Service and Troubleshooting refer to FA4A FB4A FFID FH4A AND FX4A Circuit Board Function and Troubleshooting on page 2 For FF1D typical wiring diagram see Fig 19 WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Before installation or servicing system always turn off main power to system There may be more than 1 disconnect switch Turn off accessory heater power if applicable PROCEDURE 1 FAN MOTOR The motor is 2 speed direct drive High speed lead is black low speed lead is red and common lead is violet Be sure proper blower speed has been selected For units with electrical heat low speed tap can be used For cooling use high speed tap The motor is turned on through 2 different routes The first occurs when thermostat calls for the fan in cooling heat pump or fan only mode A 24 vac signal is sent to relay causing rela
20. Reassemble cutoff plate to housing using identified holes from disassembly procedure 3 Position motor and mount in same position as when blower housing was in unit Secure motor mount on housing using removed bolts Make sure mount or motor is grounded to blower housing 4 Locate blower wheel setscrew over flat on motor shaft Rotate wheel in housing It should not rub housing and should be centered in inlet opening If not loosen setscrew and align as necessary 5 Attach green wire to blower housing with screw 6 Secure motor capacitor under strap and tighten strap screw gt CAUTION NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING 150V TO GROUND SEE RATING PLATE FOR VOLTS amp HERTZ ENTION FIELD POWER WIRING NE CONVIENT PAS AUX INSTALLATIONS DE PLUS DE 150 TERRE COOLING CONTROLS SEAS EAT COMPONENT ARRANGEMENT 0 _ SEENOTE DISCONNECT PER 15 15 b d 1 3 C Hm ul 5i o d n o9 SYSTEM TRANSFORMER 40 0VA 21 gl o GND 9 aa FAN H a aw REMAINING VA AVAILABLE 31 6VA 1 SEE NOTE 6 1 COM O YE BLK RELAY 24V 208
21. Recover any remaining refrigerant NOTE All outdoor unit coils will hold only factory supplied amount of refrigerant Excess refrigerant such as in long line applications may cause compressor internal pressure relief valve to open indicated by sudden rise in vapor pressure before vapor pressure reaches 5 psig 35kPa If this occurs turn off electrical supply to outdoor unit immediately front seat vapor service valve and recover any remaining refrigerant 3 4 Turn off electrical supply to indoor unit Disconnect condensate drain tube Disconnect liquid and vapor tubes from indoor coil Use either a tubing cutter to cut tubes or a torch to unbraze tubes as required NOTE If a torch is used to unbraze line set protect fitting panel with a wet cloth or braze shield as necessary System contains oil vapors which may ignite when exposed to a flame Remove coil access and fitting panels Remove screw securing coil to unit casing Remove coil pan assembly from unit Place assembly on a flat surface Remove 2 screws securing coil support columns to pan See Fig 44 Rotate columns 90 pull away from coil and remove columns from assembly Remove remaining 2 screws securing coil to condensate pan Remove coil from condensate pan Remove coil top seal See Fig 44 13 Install new coil into condensate pan using 2 original screws and 2 support columns NOTE Correct coil position in condensate pan is
22. UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Do not use caustic household drain cleaners in condensate pan or near coil Drain cleaners can quickly destroy coils C Blower Motor and Wheel Clean blower motor and wheel when cooling coil is cleaned To clean or service wheel or motor proceed as follows Pull unit disconnect when used and remove blower access panel Disconnect motor electrical leads from control box and capacitor Mark location of wires for reassembly 2 3 Remove 3 bolts holding motor mount to blower housing while supporting motor shell with hand 4 Pull motor inlet ring and blower wheel assembly out of blower housing 5 With blower wheel inlet ring and motor mount still attached to motor place motor on flat horizontal surface shaft up Mark position of wheel on motor shaft for reassembly 6 Loosen blower wheel setscrew and remove blower wheel from motor shaft NOTE Further disassembly of motor and mount is not necessary as adequate clearance is available to clean motor Fj BLOWER WHEEL INLET RING LE MOTOR Fig 22 FF1A FF1B FF1C Motor Inlet Ring and Blower Wheel Assembly 7 Clean blower motor and wheel using a vacuum with a soft brush attachment Remove grease with a mild solvent such as hot water and detergent Be careful not to disturb balance weights clips
23. and minimize possible equipment failure it is essential periodic maintenance be performed on this equipment The ability to properly perform maintenance on this equipment requires certain mechanical skills and tools The only consumer service recommended or required is filter maintenance See Filter Assembly WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect all power to the unit before servicing the field wires or removing the control package The disconnect when used on the access panel does not disconnect power to the line side of the disconnect but does allow safe service to all other parts of the unit The minimum maintenance requirements for this equipment are as follows 1 Inspect and clean or replace air filter each month or as required 25 Table 9 Advanced Troubleshooting Fan Coil Furnace 2 Spd Communication Bus Voltage Readings With board power applied and no U I connected A to B 3 vdc A to C 3 vdc B to C 01 to 0 3 C to D 24 vac FE Control Board 02 Furnace Control Board HK42FZ022 Two Speed Control Board HK38EA001 2 Inspect cooling coil drain pan and condensate drain each cooling season for cleanliness Clean as necessary An inspection port is provided on all A coil delta plates Remove plastic plug to inspect Replace plug after inspection 3 Inspect blower motor and wheel for cleanliness each heating and
24. or lint vacuum with a soft brush attachment Be careful not to bend coil fins If coil is coated with oil or grease clean it with a mild detergent and hot water solution Rinse coil with clear water Be careful not to splash water onto insulation Inspect drain pan and condensate drain at same time cooling coil is checked Clean drain pan and condensate drain by removing any foreign matter from pan Flush pan and drain tube with clear water Clear drain line if restricted NOTE There MUST be a trap in condensate line Trap must be at least 3 in deep not higher than the bottom of unit condensate drain opening and pitched downward to an open drain or sump B Blower Motor and Wheel Clean blower motor and wheel when cooling coil is cleaned Lubricate motor every 5 years if motor is used on intermittent operation thermostat FAN switch at AUTO position or every 2 years if motor is in continuous operation thermostat FAN switch at ON position Remove motor to lubricate Put approximately 8 drops of SAE 10 nondetergent oil in each oil hole Do not over oil motor Plug hole securely so that oil does not drip when hinged access panel is lowered to open position Blower motor and wheel may be cleaned using a vacuum with a soft brush attachment Remove grease with a mild solvent such as hot water and detergent Be careful not to disturb balance weights clips on blower wheel vanes Do not drop or bend wheel as balance will be affected FG3A SERVICE AND TR
25. BLK a Le rue YEL 8 68 HA OF RELAY 1 RELAY 2 1 2 eue 22 VDC COIL RELAY 2 BLU TDR 6 ELAY 3 i RELAY 1 22 VDC COIL mm T 22 VDC COIL RED BRN 1 oli R 1 Lr TDR d cy BRN RELAY 3 PLUG 4 9 9 OND NOE 9 61 4 PCB 9 6 1 4 210 BRN Heol SPT CIR RED LOW BRN e o FM V uu O YEL ws GND BLK HI YEL CO 85 5 ij GRNYELGND ELCOM 6 VEL 5 a Jz SEE NOTE 6 ERN TE FAN MOTOR THERMALLY PROTECTED 1 LEGEND 1 COM mur RED 9 M SEE NOTER CAP CAPACITOR HTR HEATER T SQ RT NOTES 81 Com COMMON LS LIMT SWITCH YEL BARRIER 7 LOW VOLTAGE FUSE MARKED TERMINAL e NSR crue PPN 3 gt PLUG amp RECEPTACLE MED BLU GND INDOOR OUTDOOR FM FAN MOTOR PCB PRINTED CIRCUIT BOARD 10 RED THERMOSTAT UNIT FIELD POWER WIRING PEG RECTIFIER FR NOTES HELSY DELAY RECTIFIER 1 Use copper wire 75 C min only between disconnect switch and unit GND EQUIPMENTGROUND TRANSFORMER 2 To be wired in accordance with N E C and local codes FAN SPEED TAP 3 If any of the original wire as supplied must be replaced use the same or equivalent type wire SPT LOCATION O UNMARKED TERMINAL 4 Replace low voltag
26. BRN FIELD POWER SEIS VIO CHASSIS 77 RED BLU BLK ROUND RED TRANS RED TRANS ORN BRN GT BRN BRN CHASSIS GROUND A RED 3 G CHASSIS e BRN GROUND OPTIONAL IFR TDR COMPONENT ARRANGEMENT 9 TRANS 24V 51 152 M 1 BLK 208 230 COM BLU RED DISCONNECT HTR2 px 2 5 WHEN EQUIPPED 4 6 WHEN EQUIPPED xb CHASSIS GROUND MOTOR SPEED SELECTION HI BLACK LOW RED COMMON VIO FIELD WIRE TEMP HEAT PKG SIZE RATING 2 KW 14 90 C 3 KW 12 90 C 5 KW 10 90 C 7 5 KW 8 90 C 11 KW 6 90 C 0 COOLING 14 90 C LEGEND 9 O UNMARKED TERMINAL LS LIMIT SWITCH FR FAN RELAY IFR INDOOR FAN RELAY IFR TD INDOOR FAN RELAY TIME DELAY SEQ SEQUENCER CAP CAPACITOR HTR HEATER TRANS TRANSFORMER FIELD POWER WIRING o oo OPTIONAL WIRING FUSE Hz CHASSIS GROUND NOTES UNIT WIRED FOR 230V OPERATION USING BLACK AND RED TRANSFORMER PRIMARY LEADS FOR 208V OPERATION USE BLACK AND BLUE TRANSFORMER PRIMARY LEADS AND LOOPED UNUSED TRANSFORMER LEADS MUST BE TAPED IF ANY OF THE ORIGINAL WIRE AS SUPPLIED MUST BE REPLACED USE THE SAME OR EQUIVALENT WIRE ONLY FIELD WIRING USE COPPER CONDUCTORS FAN RELAY 4 IS A DEAD TERMINAL FO
27. By observing LED status light the number of operating stages of electric heat can be determined The control also varies indoor fan speed depending on number of energized stages of heat In general the more stages of electric heat the higher the fan speed There is no hard and fast rule for determining exactly when stages will be energized since microprocessor in the smart control constantly monitors duration of previous heating cycle setting of room thermostat and number of stages of heat needed in previous cycle to satisfy room thermostat Rather than try to determine what should be operating when service technicians should check LED status light to see how many stages of electric heat are energized at a given time and confirm operation of sequencer relay using a voltmeter If a quick check of all stages is desired set room thermostat as high as it will go With a constant signal on W2T terminal sequencers relays energize every 10 minutes until all heaters are on The previous paragraphs described how to check for low voltage inputs to control by placing voltmeter leads across low voltage terminal strip and checking for 24v The call for electric heat can be confirmed by placing voltmeter leads across W2T and C To check for operation of sequencers relays check directly across appropriate coil for 24 volts DC NOTE All sequencer relay coils are powered by 24 volts DC This voltage is generated internally by the smart control In this example
28. Interlock The fan will also turn on whenever there is any call for electric heat even if the fan relay is not energized This happens because the fan is interlocked with the first stage of electric heat through the normally closed contact of the fan relay D Electric Heat When the thermostat calls for electric heat a 24 v signal is sent to the PCB through W2 causing the first stage to turn on W3 and E also receive the signal if the tabs are not broken off the PCB The signal sent to W2 causes the first stage to turn on If the tabs are broken off the PCB the sequencers can be controlled individually to stage the electric heat The sequence control is described in the following section 1 W2 When the thermostat sends a signal to W2 a 24 v dc signal is applied across sequencer number 1 causing it to close When sequencer number closes the first stage of electric heat energizes after a short delay In straight electric heat the fan is also energized through the normally closed contacts of the fan relay In cooling heat pump or manual fan mode the fan will already be running since the fan relay would have been energized When the thermostat stops calling for electric heat the 24 v dc signal to sequencer number 1 turns off and the sequencer opens after a delay of 60 to 90 sec When the sequencer opens the first stage of heat turns off along with the fan providing that the thermostat is not calling for the fan Note that the electric heat cann
29. NOTE Humidistat must open on humidity rise Latent capacities for systems using the FK4 FV4 and 40FK fan coils are better than average systems If increased latent capacity is an application requirement the field wiring terminal block provides connection terminals for use of a standard humidistat The FK4 FV4 and 40FK fan coils will detect the humidistat contacts opening on increasing humidity and reduce its airflow to approximately 80 percent of nominal cooling mode airflow This reduction will increase the system latent capacity until the humidity falls to a level which causes the humidistat to close its contacts When the contacts close airflow will return to 100 percent of the selected cooling airflow To activate this mode remove jumper J1 and wire in a standard humidistat See Fig 15 Carefully consult product airflow data for cooling and dehumidification modes FE4 Model FE4A fan coil is designed to be installed with a communicating user interface The FE4A fan coil will provide airflow at a rate commanded by the User Interface The nominal airflow ton rate is 350 CFM ton The User Interface will modify the commanded airflow under certain operating modes Refer to the User Interface literature for further system control details This fan coil will not respond to commands from a common thermostat except under certain emergency situations explained in this document PROCEDURE 1 ELECTRONICALLY COMPUTED MOTOR ECM2 5 An 2 5 is fed
30. VOLTS amp HERTZ B PLUG YEL YEL BLK 1 185 HTRS BLK 93 10H 9 COOLING CONTROL WIRING COOLING CONTROL ONLY BLK BLK BLK 8H H7 AUX HEAT RANGE CB FU4 L 183 BK GE BLK X AC HP SIZE B 24VAC a YEL VEL 492 BLK BLU gt CB FU1 TYPE o CB FU2 45 MI Bue HP COMFORT lt pe mt O AC HP CFM TRIM A gt 77 BLK AC HP DELAY ON OFF A EIB 0 30 30 30 30 30 0 0 8 _ BLU 7 O 12 2 456650609 lt pd 17 9 8 F BPN RECP 2 JWI SEC2 2 1 PLUG 1 RED 5 SEC AUXI HUMI BLK p VA ag wo EXXXXXXX 4 4 AUX HUM2 INDOOR THERMOSTAT BLU 2 RECP 1 RED 73 PCB PLUG 2 SEE NOTE 3 YEL GRN YEL Q OCOD PLUG 3 RECP 3 TEL 7 BRN RED RED ceps ops 2 Ve PLUG 4 8 7 6 5 4 210 BLU LORN BAN 4 2 BLK GRY 2 2 NOTES LEGEND 1 Use copper wire only between disconnect switch and unit 2 Connect to to etc in pattern shown MARKED TERMINAL LS LIMIT SWITCH 3 Transformer primary leads BLUE 208V RED 230V UNMARKED TERMINAL ICM FAN MOTOR 4 To be wired in ac
31. and thermostat wiring See Fig 11 and 13 Be sure transformer is not shorting out because thermostat wires are miswired 2 Check wiring of relays See Fig 11 and 13 Be sure low voltage and high voltage wiring are connected to proper sequencers 3 Check VA draw on transformer If VA draw is more than VA rating of transformer fuse will blow If this is the case replace transformer with one that has a higher VA rating B Troubleshooting Common Problems Airflow Too Low Y1 instead of Y Y2 on single speed air conditioner or heat pump application Y1 input is only for 2 speed applications Using this terminal will deliver about 60 of full cooling airflow Wrong Easy Select Board selection Selecting an outdoor unit or electric heater smaller than actually installed will result in low airflow for the application G not energized with call for cooling or heating This triggers Super Comfort Heat or SuperDehumidify mode which delivers 50 of cooling airflow jumper pulled with Thermidistat or dehumidistat installed The 71 jumper ties the DH terminal to and is installed at the factory When pulled a Thermidistat or dehumidistat supplies a 24 volt signal to DH when there is no call for dehumidification reverse logic When there is no signal on DH the motor reduces airflow to 80 for better dehumidification Airflow Too High Wrong Easy Select Board selection Fan coil is factory set for the largest outdoor unit and largest elect
32. calls for the fan the signal sent to relay is turned off and relay opens causing fan to turn off after a 90 sec fan off delay b Sequencer Electric Heat Relay Interlock The fan will also operate whenever there is a call for electric heat even if fan relay is not energized This happens because fan is interlocked with first stage of electric heat through the normally closed contact of fan relay NOTE The fan interlock is only connected to first stage electric heat W2 W3 and E do not contain an interlock with fan See outdoor thermostat Installation Instructions when electric heat staging is desired C Electric Heat When thermostat calls for electric heat a 24 vac signal is sent to sequencer heat relay through W2 causing first stage to turn on W3 and E also receive signal if wired in with W2 If W3 and E are not wired to W2 the sequencers heat relays can be controlled individually to stage additional electric heat The sequence control is described in the following section 42 T e E S 8 LOW 9 C VOLTAGE 5 FUSE PCB BLOCK WIRING D ane e T R Bs gt u TIME R6 2 3 DELAY gt 71 LE R8 C5 gt C gt 5 gt 5 D2 1 2 ga 55 1M LR40061 FAN RELAY A97020 Fig 29 Fan Coil Printed Circuit Board CES01
33. connections on primary side of transformer If they are not connected properly the transformer secondary cannot supply the 24 v signal to energize fan relay If transformer is receiving correct primary voltage but is not putting out correct secondary voltage transformer needs to be replaced B If Electric Heat Stages Will Not Turn On But Fan Will Turn On IF THERE IS NO HIGH VOLTAGE TO TRANSFORMER Check plug connection between heaters and board This supplies power to transformer and fan Be sure plug is connected properly 2 Check sequencer relay number 1 and plug wiring Yellow wire should be connected to pin number 9 of plug and to limit switch Black wire should be connected to pin number 7 of plug and to sequencer relay number 1 3 Check incoming high voltage power leads If these are not receiving power system cannot function IF TRANSFORMER HAS HIGH VOLTAGE APPLIED TO IT 1 Check low voltage transformer leads R red and C brown Make sure they are wired to correct location The unit will not function without proper connections 2 Check output voltage of transformer secondary side R red and C brown If transformer output is low less than 18 vac refer to items 3 and 4 of previous If Transformer Has High Voltage Applied To It section IF TRACES ARE OVERHEATED ON BACK OF PCB Usually whenever a trace is blown on PCB it means either there has been a high voltage short or high voltage has been applied to low voltage ci
34. cooling season Clean as necessary 4 Inspect electrical connections for tightness and controls for proper operation each heating and cooling season Service as necessary A CAUTION CUT HAZARD Failure to follow this caution could result in personal injury As with any mechanical equipment personal injury can result from sharp metal edges Be careful when removing parts PROCEDURE 1 FILTER ASSEMBLY To clean or replace air filter push plastic connectors toward center of unit and remove filter access panel outward Push filter up and back into unit Then slide filter out Clean filter by using cold water and mild detergent Rinse and allow filter to dry No oiling or coating of filter is required New filters are available from your local distributor Place filter in slot with cross mesh binding up or facing cooling coil and replace filter access panel PROCEDURE 2 COOLING COIL DRAIN PAN AND CONDENSATE DRAIN The cooling coil is easily cleaned when it is dry Inspect the coil and clean if necessary before each cooling season To check or clean cooling coil remove coil access panel If coil is coated with dirt or lint vacuum it with a soft brush attachment Be careful not to bend coil fins If coil is coated with oil or grease clean it with a mild detergent and water solution Rinse coil thoroughly with clear water Be careful not to splash water on insulation Inspect drain pan and condensate drain at the same time cooling coil is
35. deformation of the piston body will occur causing the piston to lodge in a partially open or closed position LIQUID TUBE STRAINER In R 22 units the TXV and refrigerant flow control device is protected on the indoor coil by a wire mesh strainer It is located inside the 3 8 in liquid tube at field braze joint just outside unit casing Access to strainer is through field braze joint FA FB FC COIL CONDENSATE PAN REMOVAL AND REPLACEMENT PROCEDURE 1 A COIL UNITS If it is determined that system does not have leaks and refrigerant is not contaminated proceed as follows Recover system refrigerant a Attach manifold gage set to service valves b Front seat close liquid tube service valve Start unit in cooling mode d Run unit until low pressure switch opens at 27 psig or vapor pressure reaches 5 psig 35kPa Do not allow compressor to pump into vacuum e Turn off electrical supply to outdoor unit f Front seat vapor service valve g Recover any remaining refrigerant NOTE All outdoor unit coils will hold only factory supplied amount of refrigerant Excess refrigerant such as in long line applications may cause compressor internal pressure relief valve to open indicated by sudden rise in vapor pressure before vapor pressure reaches 5 psig 35kPa If this occurs turn off electrical supply to outdoor unit immediately front seat vapor service valve and recover any remaining refrigerant 2 Turn off ele
36. essential to reliable operation 14 15 16 17 18 19 Install new coil pan assembly into unit Secure with 2 screws previously removed from unit casing Reinstall coil access and fitting panels Reconnect liquid and vapor refrigerant tubes and condensate drain tube Install new liquid line filter drier Evacuate tube set and indoor coil to 500 microns back seat open liquid and vapor service valves Turn on electrical supplies to indoor and outdoor units Check system refrigerant charge and operation See Split System Residential Air Conditioners and Heat Pumps Service Manual for further information FX4 AND FV4 COIL CONDENSATE PAN REMOVAL AND REPLACEMENT PURON REFRIGERANT PROCEDURE 1 4A COIL UNITS If it is determined that system does not have leaks and refrigerant is not contaminated proceed as follows 1 Recover system refrigerant a Attach manifold gage set to service valves COIL MOUNTING SCREW SLOPE A DRAINPAN REFRIGERANT COIL TO CONNECTIONS PAN SCREW BOTH SIDES A98113 Fig 44 Slope Coil Component Location 61 b Front seat close liquid tube service valve c Start unit in cooling mode d Run unit until low pressure switch opens 350kPa or vapor pressure reaches 5 psig 35kPa Do not allow compressor to pump into a vacuum e Turn off electrical supply to outdoor unit f Front seat vapor service valve g Recover any rema
37. heat The 24 vac signal applied to sequencer relay number 1 turns on first stage of electric heat and fan When thermostat stops calling for electric heat the signal to sequencers relays 1 2 and 3 are turned off and sequencers relays open This causes electric heat to turn off with fan providing thermostat is not calling for the fan NOTE Electric heaters are factory wired with all stages tied together If independent staging is desired consult outdoor thermostat installation instructions or corporate thermostat instructions PROCEDURE 3 TROUBLESHOOTING THE PRINTED CIRCUIT BOARD CES013000 00 01 HK61EA002 Use wiring schematics shown in Fig 30 and 29 as a guide in troubleshooting PCB unless otherwise noted If Fan Will Not Turn On from Thermostat IF THERE IS NO HIGH VOLTAGE TO TRANSFORMER 1 2 3 Check plug receptacle connection This supplies power from heaters to PCB Fan Relay Be sure plug is connected properly Check sequencer relay number 1 and plug wiring Yellow wire should be connected to pin number 9 of plug and to limit switch Black wire should be connected to pin number 7 of plug and to sequencer relay number 1 Check field power leads L1 and L2 If these are not receiving power system cannot function If Transformer Has High Voltage Applied To It 1 2 3 Check low voltage transformer leads R red and C brown Be sure they are wired to correct locations Check output voltage of transformer
38. in Fig 39 Make sure the low voltage and the high voltage wiring are connected to the proper sequencers 3 Check the VA draw on the transformer If the VA draw is more than the VA rating of the transformer the fuse will blow If this is the case replace the transformer with 1 that has a higher VA rating and meets system specifications G The fan runs continuously 1 If the PCB has no low voltage power check the blue and black fan leads These may be switched at the sequencer 2 If the PCB has low voltage power check the fan relay to see if it is opening and closing It may be stuck in the normally closed position due to debris in the relay BLOWN DIODE b BLOWN DIODE a BLOWN DIODE FUSE 24VDC 2 000 perm RELAY TRANSFORMER AC LINE DUMMY F2 T T2 T3 12 EAC2 DUMMY COMMON DUMMY FAN Li COMMON 240 VAC 240 VAC Lo A97033 Fig 40 Control Board Noting Diodes HK1GA001 H Transformer failure 1 Check 208 v and 240 v taps connected 10 and They may be miswired Replacement Motor Position The position of the blower motor should be properly located in the blower housing to reduce any frequency pulsations The position is generated based upon
39. on blower wheel vanes Do not drop or bend wheel as balance will be affected A86006 To reassemble unit proceed as follows 1 Place motor with mount attached on flat horizontal surface with shaft up 2 Set inlet ring on top of motor mount grommets Center inlet ring flush on all 3 grommets 3 Slide blower wheel onto motor shaft with setscrew upward and aligned with shaft flat portion Vertically position wheel along shaft to position marked during disassembly NOTE If previous shaft was not marked or if replacing previous motor set blower wheel position by sliding blower wheel along motor shaft to 1 1 8 in above rubber grommets See Fig 22 4 Hold blower wheel in place and carefully tighten setscrew Position motor and blower wheel assembly to blower housing as originally oriented Secure motor mount to blower housing using bolts previously removed Attach green wire to blower housing with screw Connect electrical and capacitor leads to original terminals Replace blower access door and tighten all 4 screws 10 Reinsert disconnect pullout only after blower access door is secured Test blower for proper operation FD3A SERVICE AND TROUBLESHOOTING WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Before installation or servicing system always turn off main power to system There may be more than 1 disconnect switch Turn off a
40. operational modes See Fig 11 C System Type The type of system must be selected 1 conditioner approx 350 2 HP COMFORT provides lower airflow than air conditioner selection approximately 315 CFM ton in heating mode In cooling mode supplies 350 CFM ton 15 Table 7 Typical Operating Modes Operating Terminals Energized Mode Heat Pump Only Heating Super Comfort Heat Mode Heat Pump Heating Auxiliary Heat non staged Cooling Dehumidification Cooling Superdehumidify 3 HP EFF provides same airflow for heat pump heating and cooling modes approximately 350 CFM ton The factory setting is AC See Fig 11 D AC HP CFM Adjust Select low nominal or high airflow The factory selection is NOM The adjust selections HI LO will regulate airflow supplied for cooling and heat pump heating modes only 15 percent and 10 percent respectively The adjust selection options are provided to adjust airflow supplied to meet individual installation needs for such things as noise comfort and humidity removal See Fig 11 E ON OFF Delay NOTE ON OFF Delay is active only in cooling and heat pump only heating modes In auxiliary heat mode or emergency heat mode the ON delay is 0 seconds and the OFF delay is fixed and cannot be overridden Select desired time delay profile Four motor operation delay profiles are provided to customize and enhance system operation See Fig 11
41. profile will minimize cold blow in heat pump operation and could enhance system efficiency 4 ENH enhanced selection provides a 30 sec on 180 sec off delay at half airflow adding comfort and efficiency PROCEDURE 5 TROUBLESHOOTING CIRCUIT BOARD FK4B Use Fig 5 and 6 and Tables 3 4 5 and 6 as guides in troubleshooting PCB unless otherwise noted A If Fan Will Not Turn On From Thermostat IF THERE IS NO HIGH VOLTAGE TO PCB 1 Check connection of 12 pin plug from heaters to receptacle on Easy Select board This supplies power to PCB Be sure plug is connected properly 2 Check sequencer number 1 and plug wiring Yellow wire should be connected to pin number 9 of plug and to limit switch Black wire should be connected to pin number 7 of plug and to sequencer number 1 3 Check power leads L1 and L2 If these are not receiving power system cannot function IF PCB HAS HIGH VOLTAGE APPLIED TO IT 1 Check low voltage transformer leads red and brown Be sure they are wired to correct locations See Fig 14 and 18 2 Check output voltage of transformer secondary side SEC2 and SECI Be sure transformer output is around 24 vac If transformer output is zero vac and transformer is receiving correct input voltage 208v or 240v then transformer needs to be replaced with recommended transformer If transformer output is 24 vac proceed to items 3 and 4 3 Check low voltage fuse shown in Fig 4 If fuse is blown replace it The transf
42. secondary side R red and C brown Be sure transformer output is between 18 and 30 vac If transformer output is incorrect and transformer is receiving correct input voltage 208v or 230v then transformer needs to be replaced with recommended transformer If no problem exists with transformer secondary proceed to items 3 and 4 Check low voltage fuse shown in Fig 29 If fuse is blown replace it with an identical 5 amp fuse The transformer cannot supply power to board with fuse blown or loose If fuse blows when unit has power applied to it the system most likely has 1 of the following problems a Check all 24 v wiring for an electrical short 43 THIS COMPARTMENT MUST CLOSED EXCEPT FOR SERVICING CAUTION gt NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING BLOWER MOTOR 150V TO GROUND ROTATION ATTENTION 30KW SCHEMATIC DIAGRAM LEGEND FIELD POWER WIRING DISCONNECT PER NEC CAP CAPACITOR 5 LIMIT SWITCH Pro COM COMMON MARKED TERMINAL SEE RATING PLATE h h h FOR VOLTS amp HERTZ LOW VOLTAGE FUSE PLUG AND RECEPTACLE GND FANMOTOR PCB PR
43. the blower motor as long as User Interface maintains a demand for airflow Fan coil control will not operate electric heaters while a fault condition exists The fan coil control communicates with the motor at least once every 5 seconds even when the motor is idle If during operation the fan coil control does not communicate with the motor for more than 25 seconds the motor will shut itself down and wait for communications to be reestablished D Using Motor LED in Troubleshooting The MOTOR LED is connected to the blower motor communication line and works with the fan coil control microprocessor and the STATUS LED to provide fan coil operation and troubleshooting information When the motor is commanded to operate the MOTOR LED will be turned on and will flash each time instructions are sent to the motor When the motor is commanded to stop the MOTOR LED will be turned off If the MOTOR LED is lit flashing and the motor is running or if the MOTOR LED is off and the motor is stopped operation is normal and no motor fault exists If the MOTOR LED is lit flashing and the motor does not run or if the MOTOR LED is off and the motor is running check the STATUS LED for the Status Code Refer to the troubleshooting instructions for the indicated Status Code in Section E Fan Coil Troubleshooting E Fan Coil Troubleshooting Fan coil faults indicated by flashing codes on the amber system STATUS LED can be resolved using troubleshooting information pro
44. to the low voltage circuit This can be prevented by making sure the PCB is wired correctly before the PCB has power applied to it E If there are blown diodes 1 If diodes a and b are blown it is probable the electric heater plug was miswired Correct the miswiring It should be noted the board will need to be replaced if the diode indicated is bad 2 If any of the diodes are blown the fan 15 miswired to 1 of the low voltage terminals AUX1 or AUX2 Check to make sure that the fan leads are connected to the proper terminals as shown in Fig 39 If the fan is connected properly make sure that no other high voltage is applied to the AUX terminals F The PCB fuse keeps blowing When the low voltage fuse blows it means the transformer would have just blown if the fuse had not been in the circuit to protect it The fuse usually blows when there is a high current draw on the transformer high voltage applied to the low voltage circuit or a direct secondary short When there is a high current draw on the transformer it is most likely because the transformer has been shorted or the system is trying to draw more VA than the transformer is rated for When the fuse blows because of high voltage the system has mixed high and low voltage signals 1 Check the transformer and thermostat wiring as shown in Fig 37 Make sure the transformer is not shorting out by the thermostat wires being miswired 2 Check the wiring of the sequencers as shown
45. troubleshooting elements position thermostat to emergency heat Wait approximately 12 minutes after all thermostat delays for all elements to come on 1 When thermostat calls for supplementary heat a 24 v signal is sent to PCB through W2T The PCB energizes first stage of electric heat 37 CAUTION N NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING 150V TO GROUND ATTENTION NE CONVIENT PAS AUX INSTALLATIONS DE PLUS DE 150 V A LA TERRE THIS COMPARTMENT MUST CLOSED EXCEPT FOR SERVICING BLOWER MOTOR ROTATION SCHEMATIC DIAGRAM COMPONENT ARRANGEMENT FIELD POWER WIRING DISCONNECT PER NEC SEE RATING PLATE iri FOR VOLTS 8 HERTZ 4 2 SEE NOTE 1 x to 157 isd 5 5 5 e SEQ3 e e z In g YEL ALS3 A HTR3 gi SEQ 1 BLK EC 2 509 SYSTEM TRANSFORMER 40 0VA COIL HEATER 26 3VA BLK 152 SEQ REMAINING VA AVAILABLE 1374 L Osee C ERN H Jasov 1817 BLK Ss BLK x Y e Ww ve OLED 9 wa _ 58514 54 918 7 J p AUX 0 950 604 Fi Om H O
46. zoning have the capability of both of these modes To initiate these operating modes the control drops out the G signal to reduce airflow for extra comfort in heating and maximum dehumidification in cooling This must be kept in mind while troubleshooting these fan coils Be aware that a cooling or heating input without the G input energized will result in significantly lower airflow than may be expected When verifying airflow in normal heating and cooling modes including emergency heat in newer motors remember that G must be energized to achieve full airflow Table 5 Motor amp Modules Capable of Comfort Heat SuperDehumidfy Modes Model Motor Part Number Replacement Module Part No FV4A 40 01 002 HD44AE128 131 125 RMOD44AE128 131 FK4C FV4A 40FKA003 HD44AE129 132 127 RMOD44AE129 131 FK4C FV4A 40FKA005 HDD44AE130 133 126 RMOD44AE130 133 FK4C FV4A 40FKA006 HD46AE243 244 242 RMOD46AE243 244 These motors will not adjust airflow with G in electric heat modes The FK4 has some earlier series that were produced before the Comfort Heat Pump System was introduced Some of the motors will not have the programming that slows the fan down on a loss of the G signal The following units are factory programmed for Super Comfort Heat and SuperDehumidify Modes FKAC Series A through E 1995 1997 NONE FKAC Series F reduces airflow in heat pump heating and cooling mode
47. 1 and 2 IF THERE ARE BLOWN DIODES If diodes are blown it is probable that electric heater plug is miswired Correct miswiring NOTE Board will need to be replaced if diode is bad IF TRACES ARE OVERHEATED ON BACK OF PCB Usually whenever there is a trace blown on PCB it means either there has been a high voltage short or high voltage has been applied to low voltage circuit This can be prevented by making sure PCB is wired correctly before PCB has power applied to it C If PCB Fuse Keeps Blowing When low voltage fuse blows it means transformer would have blown if fuse had not been in circuit to protect it The fuse usually blows when there is a high current drawn on transformer high voltage applied to low voltage circuit or a direct secondary short When there is a high current drawn on transformer it is most likely because transformer has been shorted or system is trying to draw more VA than transformer rating allows When fuse blows because of high voltage the system has mixed high and low voltage signals 1 Check transformer and thermostat wiring See Fig 4 and 6 Be sure transformer is not shorting out because thermostat wires are miswired 2 Check wiring of sequencers See Fig 4 and 6 Be sure low voltage and high voltage wiring are connected to proper sequencers 3 Check VA draw on transformer If VA draw is more than VA rating of transformer fuse will blow If this is the case replace transformer with one that has a
48. 30V 4 OF THE ORIGINAL WIRE AS SUPPLIED MUST BE REPLACED VEL YEL 182 2 BLK BLK USE THE SAME OR EQUIVALENT TYPE WIRE 5 REPLACE LOW VOLTAGE FUSE WITH NO GREATER THAN 5 AMP FUSE CBFUI SEQ 1 2 6 20KWHEATER USES ONE DOUBLE POLE LS ON MIDDLE TOP ELEMENT YEL LS BLK gt 7 18 24 AND 30KW HEATERS USE DOUBLE POLE LIMIT SWITCHES 8 LARGEST HEATERS ARE SHOWN SMALLER HEATERS WILL HAVE FEWER ELEMENTS AND COMPONENTS BRN 9 1 PHASE HEATERS ARE SHOWN WIRED FOR SINGLE SUPPLY CIRCUIT RED 10 USE 60 AMP CLASS FUSES ONLY FOR REPLACEMENT 11 8 SPEED MOTOR SHOWN OPTIONAL 2 SPEED MOTOR USES BLK AND LOW O BRN BLU OR RED GRAY 12 CONNECT R TOR G G ETC SEE OUTDOOR INSTRUCTION FOR DETAILS 13 IF WIRE CRIMP IS REMOVED AN EMERGENCY HEAT RELAY 5 REQUIRED 9 17 3 2 861 4 C SEE OUTDOOR THERMOSTAT INSTRUCTIONS 321214101 REV C 208 240VAC 24 24VAC A94346 Fig 30 Wiring Diagram of 6 Element Sequencer Heater b The maximum load on transformer is 40 VA If load on transformer is excessive the low voltage 5 amp fuse will blow to protect transformer If load exceeds VA rating of transformer a larger VA rated transformer needs to be installed Check sequencers relays for excessive current draw c Check wiring of heaters If a heater is miswired fuse may blow If a heater is miswired correct miswiring by comparing it to heater wiring label 4 Check
49. 3C00 00 01 HK61EA002 1 W2 When thermostat sends a signal to W2 a 24 vac signal is applied across sequencer relay number 1 causing it to close When sequencer relay number 1 closes first stage of electric heat is energized In straight electric heat fan is also energized through the normally closed contacts of fan relay In cooling heat pump or manual fan mode fan will already be running since fan relay would have been energized When thermostat stops calling for electric heat the 24 vac signal to sequencer relay number 1 turns off and sequencer opens after a delay of 60 to 90 sec Heaters equipped with relays will be de energized immediately When sequencer relay opens first stage of heat turns off along with fan providing thermostat is not calling for the fan When signal is sent to W3 24 vac signal to sequencer relay number 2 causes it to close with second stage of electric heat turning on The 24 vac signal applied to sequencer relay number 1 causes fan to operate Timing is such that sequencer relay number 1 will turn on before sequencer relay number 2 When signal to W3 is turned off sequencer relay number 2 opens If W2 is also satisfied first stage of electric heat and fan will also turn off providing thermostat is not calling for the fan E When thermostat sends a signal to E a 24 vac signal is sent to sequencer relay number 3 The 24 vac signal applied to sequencer relay number 3 turns on third stage of electric
50. ATIONS DE PLUS DE 150V TO GROUND 150V A LA TERRE COOLING CONTROL ONLY COMPONENT ARRANGEMENT FIELD POWER WIRING SEE RATING PLATE me PER NEC FOR VOLTS amp HERTZ SEE NOTE 1 E 2 SYSTEMTRANSFORMER 40 0 VA FAN COIL 40 VA REMAINING AVAILABLE 360 VA ABCD Use Copper Wire 75 Min Only Between Disconnect Switch And Unit Be Wired In Accordance With And LocalCodes If Any Of The Original Wire As Supplied Must Be Replaced Use The Same OrEquivaknt Wire Replace Low Vokage Fuse With Greater Than 5 Amp Fuse For Use With ommuni ting Themostat Only Connect A To A B Etc Communica ting Outdoor Units ConnectA To B To Etc TROUBLE SHOOTING NFORMATION MOTOR LED MOTOR FAULT AC TION LEGEND OFF NOTRUNNING STATUSLED OFF RUNNING MOTOR FIELD POWER WIRING ON FLASHING NOTRUNNING MOTOR HARNESS ON FLASHING RUNNING NONE Dr nu AND RECEPTACLE GND EQUIPHENTGROUND ECM FAN MOTOR OUTDOOR AIR THERMISTOR JE 8 8 6 HUM CW O Y R STATUS LED FAULT ACTION ON NONE STANDEY MODE OFF NO LOW VOLTAGE OR CONTROL CHECK PO WER AND FUSE 16 NO SYSTEM COMMUNICATIONS CHECK WIRING PCB PRINTED CIRCUTBOARD OTHER REFER TO SERVICE SCREENS ON USER INTERFACE OR THE RECP RECEPTACLE FAN COIL TROUBLESHOOTING GUIDE TRAN TRANSFORMER 328126 101 REV A A04159 2 If symptoms pers
51. CB power and electric heaters Note the pin numbers on plug 5 A time delay relay circuit keeps fan motor running for approximately 90 sec after G is de energized The time delay can be defeated by cutting jumper JW1 on the 50130003 01 and HK61EA002 PROCEDURE 2 UNIT FUNCTIONS A Transformer 1 Proper Wiring of Transformer Primary or High Side Yellow wire from Molex plug is wired to C terminal on transformer and black wire from PCB relay normally open terminal is wired to 208v or 230v terminal on transformer Units are factory wired at 230v terminal 2 Proper Wiring of Transformer Secondary or 24 v Side Red wire of transformer is wired to T terminal on PCB and brown wire of transformer is wired to C terminal on PCB NOTE T terminal on PCB is used to protect transformer T terminal is connected through the fuse to R terminal on PCB B Indoor Fan 1 Wiring Indoor fan motor yellow lead is wired to C terminal on transformer The red blue or black speed lead is wired to SPT terminal on fan relay part of PCB Units are factory wired on medium speed blue lead connected NOTE Unused fan speed leads must be capped or taped off to prevent direct short to cabinet surface 2 Functional Control a Thermostat and Relay Control When thermostat calls for the fan in cooling heat pump heating or fan only mode a 24 vac signal is sent to relay This causes the relay to close its normally open contacts turning on fan When thermostat no longer
52. ECTIONS F2 T1 T2 T3 12 EAC2 DUMMY FAN COMMON DUMMY F1 L1 1 COMMON 240 240 TRANSFORMER AC LINE O X ELECTRONIC AIR CLEANER CONNECTIONS A97026 Fig 33 HK61GA003 Printed Circuit Board e transformer The red wire provides low voltage 24v to the PCB and the thermostat R is fused on the HK61GA003 board C is used to connect the brown wire of the thermostat to provide a return path to ground through the fuse which protects the transformer is fused on HK61GA001 board is used to control the switching of the relay to turn the fan on through the normally open contact of the relay Y on the HK61GA001 is used as the junction for the outdoor section s Y connection which controls the compressor contactor for heat pump and cooling modes The HK61GA003 board contains a 90 sec fan off delay which begins timing when the Y is de energized 4 O is used as a junction for a heat pump reversing valve circuit 8 B T W2 is used to turn on the first stage of electric heat which is interlocked with the fan through the normally closed fan relay Unless the tabs are broken off all stages of electric heat will turn on when W2 receives a signal from the thermostat W3 is used to turn on the second stage of electric heat Note the W2 and W3 tab must be broken off for individual staging to take place Energizing W3 will
53. F 6SM Cancels F 5SM SM03 5 Printed in U S A 02 05 Catalog No O3FA 4A6 This symbol indicates a change since the last issue SAFETY CONSIDERATIONS Improper installation adjustment alteration service maintenance or use can cause explosion fire electrical shock or other conditions which may cause personal injury or property damage Consult a qualified installer service agency or your distributor or branch for information or assistance The qualified installer or agency must use factory authorized kits or accessories when modifying this product Refer to the individual installation instructions packaged with the kits or accessories for detailed information Follow all safety codes Wear safety glasses and work gloves Use quenching cloth for brazing operations Have fire extinguisher available Read these instructions thoroughly and follow all warnings or cautions attached to the unit Consult local building codes and National Electrical Code NEC for special installation requirements It is important to recognize safety information This is the safety alert symbol N When you see this symbol on the unit or in instructions and manuals be alert to the potential for personal injury Understand the signal words DANGER WARNING and CAUTION These words are used with the safety alert symbol DANGER identifies the most serious hazards which will result in severe personal injury or death WARNING signifies hazards which could result in person
54. FORT is selected the airflow is 315 CFM per ton The airflow will adjust up if necessary when auxiliary heating is required When both the Y Y2 and W1 or W2 terminals are energized the motor will run the higher of the heat pump or electric heat airflows During Super Comfort Heat mode the indoor control removes the G signal from the board This slows the motor to 7596 of heat pump airflow If the CFM adjust is set to LO it will deliver 67 596 of heat pump airflow during Super Comfort Heat mode 1 PROCEDURE 5 TROUBLESHOOTING A Troubleshooting Easy Select Board FK4 FV4 40FK IF TRACES ARE OVERHEATED ON BACK OF PCB Usually whenever there is a trace broken on PCB it means either there has been a high voltage short or high voltage has been applied to low voltage circuit This can be prevented by making sure PCB is wired correctly before fan coil has power applied to it If PCB Fuse Keeps Blowing When low voltage fuse blows it means transformer would have blown if fuse had not been in circuit to protect it The fuse usually blows when there is a high current drawn on transformer high voltage applied to low voltage circuit or a direct secondary short When there is a high current drawn on transformer it is most likely because transformer has been shorted or system is trying to draw more vac than transformer rating allows When fuse blows because of high voltage the system has mixed high and low voltage signals 1 Check transformer
55. GRAM FOR 2 3 amp 5 KW HEATERS SEE RATING PLATE BEK IFR TDR OPTIONAL MOTOR FOR VOLTS amp HZ 43 1 BLK DISCONNECT 4 RED BLK gt T BLK 4 EE lt 3 POWER SEQ SHEED CHASSIS RED BLU ROUND TRANS YYYY gr RED BRN Cane d wr ve BRN 6 ORN C FR JO CHASSIS cJ PRN GROUND BANS cHassis E e ORN GROUND e VIO OPTIONAL IFR TDR SEE RATING PLATE OPTIONAL MOTOR FOR VOLTS amp HZ BLK 8 DISCONNECT 4 RED BLK iu OV BLK lt 2 1 FIELD lt POWER 02 SEQ SUPPLY 3 ED SEQ SCHEMATIC DIAGRAM FOR 7 5 amp 11 KW HEATERS CHASSIS GROUND RED gr RED TRANS BRN wr NEKO ORN C FR CHASSIS GROUND RED CHASSIS ORN GROUND OPTIONAL IFR TDR SEE RATING PLATE FOR VOLTS amp HZ DISCONNECT SCHEMATIC DIAGRAM FOR COOLING CONTROL BLK 354 IFR TDR OPTIONAL MOTOR CAP
56. INTED CIRCUIT BOARD TII MM E FIELD POWER WIRING SEQ SEQUENCER FR PCB FAN RELAY TRAN TRANSFORMER es FU FUSE O UNMARKED TERMINAL 156 HTR6 BLK BLK GND EQUIPMENT GROUND RECP RECEPTACLE 4105 STO 13 1 Kt d HVTB HIGH VOLTAGE TERMBLOCK CB CIRCUIT BREAKER SEQ3 BLK HEATER 195 BLK 19 3 HTR4 BLK BLK FIELD POWER WIRING d p EE CBIFU3 5 SEQ CB FU4 15 183 BLK BLK YEL 7 BLK COOLING CONTROL ONLY Dals Oz SEQ 1 CB FU2 2 H1 BLK power BLK BRN WIRING RED YEL BLK PLUG T P 9 m7 372 51 a YEL BLU PLUG 208 240VAC 24VAC 24VAC 9 2 61 4 9 WEF 3 2 6 1 4 5 S 4 RESP RECP SCHEMATIC DIAGRAM _ SP FIELD POWER WIRING DISCONNECT PER NEC 1 1 SEE RATING PLATE FOR VOLTS 8 HERTZ YEL afafa we 1 550 YEL gt gt tt 800 3 RA RED LO DA 9 n BRN BLUMED R SEE NOTE 13 L HTR5 HZ src TRAN BARRIER SEENOTE 72 YEL 55 GRN YEL GND BRN OUTDOOR 184 HTR4 NOTES THERMOSTAT UNIT 4 8 CBFUS 1 USE COPPER WIRE 75 C MIN ONLY BETWEEN DISCONNECT SWITCH AND UNIT CBIFUS HTR3 BLK BLK 2 TOBE WIRED IN ACCORDANCE WITH NEC AND LOCAL CODES 3 TRANSFORMER PRIMARY LEADS BLUE 208V RED 2
57. L MODE 8 DO NOT CONNECT THERMOSTAT TO PCB LS LIMIT SWITCH LEADS MINIMUM MOTOR LO SPEED TAP SELECTION MARKED TERMINAL 6 FLASHES DEFROST MODE FAN COIL SIZE 030 033 036 038 042 1048 060 070 POB JUMPER JW EMERGENCY HEAT MOTOR SPEED AT 20 KW MED MED LO LO Lo Lo Lo Lo UNMARKED TERMINAL MODE J A94132 Fig 28 Smart Heat Typical Wiring Diagram Motor Speed at 20kw Shown Table 11 Electric Heater Stage Limiting Heater Part No Stages KW Operating W2T Only JW1 cut W2T W3 2 KFAEH2201H10 10 kw Non Fused 1 3 101 10 3 KFAEH2301H15 201 15 KFAEH2401H20 or 20 kw Fused 5 KFCEH0301H20 2 The first 2 stages come on if W2T and Y are energized at the same time After each 10 minutes W2T is energized another stage of electric heat is energized 3 As W2T is de energized electric heat stages down in 8 minute steps with the exception of first step The first step will be on only half as long as it was prior to W2T de energizing 4 When W2T is energized by itself JW1 is cut and an outdoor thermostat is used and is open staging is limited as in Table 11 5 When both W3 and W2T are energized without being cut or with outdoor thermostat closed system operation stages heat up to maximum level if signal is energized for proper amount of time 6 If only W3 is energized 1 is cu
58. OUBLESHOOTING PROCEDURE 1 SERVICE A Motor Ball bearing oilers are provided on blower motor Use electric motor oil or SAE 10 or 20 nondetergent oil Check motor mount bracket and base bolts Tighten as required B Blower Check ball bearings for wear Ball bearings are self aligning and grease packed Replace as required Check thrust collars for end play and alignment of wheel Check blades for accumulation of dirt Clean as required Check mounting brackets base bolts and isolation material See Fig 25 for diagram of internal wiring for blower coil assembly Control box standard 4 in junction box is mounted on refrigerant connection side of unit All leads pass through strain relief where they enter control box Wiring inside cabinet is located so it does not come in contact with moving parts or sharp edges C Pulley and Belts Check belt tension and pulley alignment See Fig 26 Belt tension is adjusted by motor tailpiece bolt A deflection of about 3 4 in to 1 in per foot of span should be obtained by pressing belt firmly Lock adjusting bolt in position after adjustment is made Align pulley grooves by locating motor pulley on motor shaft or by moving entire motor along motor mounting bracket Adjust blower speed by loosening setscrew in outer moveable pulley face and turning this face half or full turns so that adjusting setscrew is positioned precisely over the flat on pulley hub Speed is reduced by adjusting pulley faces so
59. PPLY B 2 9 2 oo SEQ 3 2 ax ONG 3 1 2 P2 BLK NO 2 2 192 FC BLK HN COMPONENT ARRANGEMENT BRN FIELD POWER WIRING YEL YEL iN OPTIONAL BRN 8 HTR 2 BRN T 4 f OPTIONAL YEL BLK DN 5 SEF NOTE 4 i EQUIP GND DISCONNECT PER N E C 3 FIELD ZA CONTROL WIRING LEGEND FIELD POWER WIRING OPTIONAL gt FIELD GROUND WIRING FIELD CONTROL WIRING FIELD SPLICE JUNCTION MARKED CONNECTION UNMARKED CONNECTION FAN CAPACITOR FAN i mul HEATE INDOOR FAN MOTOR LIMIT SWITCH QUAD TERMINAL SEQUENCER TERMINAL BLOCK wm WIRE SLEEVE TRANS TRANSFORMER FUSIBLE LINK HAOS DMI NOTES 1 TRANSFORMER PIGTAILS BLUE 208V RED 230V INSULATE UNUSED LEAD FAN MOTOR PIGTAILS RED LOW BLACK HIGH INSULATE UNUSED LEAD FAN MOTOR THERMALLY PROTECTED SUITABLE FOR USE WITH COPPER OR COPPER CLAD ALUMINUM CONDUCTORS RATED FOR 75 C MINIMUM FOR COPPER USE 6 AWG FOR COPPER CLAD ALUMINUM USE 4 AWG 40DQ500784 23 Typical Wiri
60. R UNUSED MOTOR LEAD STORAGE TO CHANGE MOTOR SPEEDS EXCHANGE THE BLACK AND RED MOTOR LEADS ON THE FAN RELAY 316596 401 REV B Fig 21 FF1A FF1B FF1C Typical Unit Wiring Label 50 91140 Table 10 PSC Fan Motor Speed Taps Size Speeds Speed Speed Speed Easa 0806 2 Blue Yellow FA4A 042060 3 Blue Red Yellow FB4A 0800 3 __ Blue Red Yellow FCB 02400 3 Blue Red Yellow FA 08090 2 Black Rea Yellow 018 030 2 Black Red Violet FGA 3 Black Red Yellow 3 Black Red Yellow Belt drive Yellow FF1D 3 Inspect blower motor and wheel for cleanliness each heating and cooling season Clean as necessary 4 Inspect electrical connections for tightness and controls for proper operation each heating and cooling season Service as necessary WARNING CUT HAZARD Failure to follow this warning could result in personal injury As with any mechanical equipment personal injury can result from sharp metal edges Be careful when removing parts A Air Filter To clean or replace air filter grasp it at bottom and lift it out of unit Clean filter using cold water Rinse clean and let dry Oiling or coating of filter is not required To replace stand filter in rac
61. SERVICE MANUAL RESIDENTIAL FAN COIL UNITS FA4 FB4 FC4 FD3 FF1 FH4 4 4 FX4 40FK TABLE OF CONTENTS Page SAFETY CONSIDERA Re qae 2 INTRODUCTION UMP UNICO VULGO E U 2 amp TROUBLESHOOTING cesare cesse aE er e E n erect yes 32 35 FG3A SERVICE amp TROUBLESHOOTING 35 36 CIRCUIT BOARD FUNCTION amp TROUBLESHOOTING 2 36 56 FA4 FC4 Smart Heat Circuit Board 36 42 FA4 FC4 FH4 FX4 5013003 00 and 01 HK61EA002 PCB 42 45 6104 001 and 003 45 56 ELECTRIC HEATER FUNCTION AND TROUBLESHOOTING 56 58 THERMOSTATIC EXPANSION VALVES 98 59 COIL AND CONDENSATE REMOVAL amp 59 63 FOR FV FA FB FC FK FAN COILS 2459 61 FOR 4 AND 4 FAN COILS 61 63 PURON QUICK REFERENCE GUIDE ies 64 A98023 Fig 1 Typical Fan Coil Form
62. THE LIMIT SWITCH When replacing limit switch ensure that it is replaced with a limit switch of identical opening temperature and closing differential Limits switches are typically color coded to identify their range 1 ii A04161 B KFA and KFB Sequencer The sequencer is essentially a thermally activated time delay relay normally activated by low voltage control signals from thermostat The typical sequencer is a 1 2 pole normally open device which energizes within 30 to 70 sec after application of control signal and de energizes 60 to 90 sec after control signal is removed In simplistic terms the sequencers which we use are nothing more than normally open limit switches which sit on top of a small resistive heater When voltage is applied to this heater a positive temperature coefficient resistor PTC heat is supplied to a bimetallic disc which snaps through and closes switch The time required for PTC to heat to a sufficient point controls ON timing of device The time required for disc to cool down when power is removed controls OFF time of device The PTC can be varied to provide varied timing Typically a short ON equates to a long OFF Because this is a thermally activated device ambient conditions affect the ON OFF cycle Higher ambient temperature means shorter ON times and longer OFF times These sequencers may be ganged up to 3 on a common mounting plate to control up to 6 heat
63. The selection options are 1 The standard 90 sec off delay factory setting 0 90 2 No delay option used for servicing unit or when a thermostat is utilized to perform delay functions 0 0 3 30 sec 90 sec off delay profile used when it is desirable to allow system coils time to heat up cool down prior to airflow This profile will minimize cold blow in heat pump operation and could enhance system efficiency 30 90 4 ENH enhanced selection provides a 30 sec on 150 sec at 70 percent airflow and no off delay F Continuous Fan Select desired Continuous fan profile LO MED or HI Airflow are provided to customize and enhance the continuous fan functions See Fig 11 The possible selections are 1 LO provides 50 of Y Y2 Cool airflow 2 MED provides 65 of Y Y2 Cool airflow 71 006 model 3 HI provides 100 of Y Y2 Cool airflow The factory setting is LO NOTE If applied to two speed unit do not select continuous fan as HI since low speed cooling will also run at HIGH airflow and insufficient dehumidification may result G Easy Select Board Jumpers This jumper must be pulled to activate dehumidification mode The jumper connects to DH With the jumper in the DH terminal is always energized With the jumper pulled the DH terminal is de energized A control such as the Thermidistat must be used to supply the 24 volt signal when there is no call for dehumidification and turn off the 24 volts when there i
64. V LS2 HTR2 BLK 2 MEK 6 230 V YEL 0 e 1 o 151 1 1 exe ae DISC PCB NOI 60 60 FR GND 2 BRN GND _BLK HI GRN YEL GND YEL COM SEE NOTE 5 FAN MOTOR THERMALLY PROTECTED LEGEND CAPACITOR EL COM COMMON HI BLK TRAN BARRIER SEE NOTE 7 BRN e LO RED GRNYEL f INDOOR ouTDOOR FM FAN MOTOR GND THERMOSTAT UNIT FIELD POWER WIRING NOTES FR PCB FAN RELAY 1 Use copper wire 75 min only between disconnect switch and unit mo EQUIPMENT GROUND 2 To be wired in accordance with nec and local codes HEATER 3 If any of the original wire as supplied must be replaced use the same or 15 LIMIT SWITCH equivalent type wire MARKED TERMINAL 4 Replace low voltage fuse with no greater than 5 AMP fuse PLUG AND RECEPTACLE 5 2 Speed Motor uses HI BLK and LOW RED PCB PRINTED CIRCUIT BOARD 6 Smaller heaters will have fewer components REC RECTIFIER 7 Connect R to R G to etc see outdoor instructions for details SPT FAN SPEED TAP LOCATION 8 Cooling controls wiring not used with electric heaters TRAN TRANSFORMER o UNMARKED TERMINAL This compartment must be closed except MINIMUM MOTOR SPEED SELECTION when servicing FAN COIL SIZE 018 024 030 MOTOR SPEED ONE LO LO L mmm ROTATION 010110 324494 101 REV
65. al injury or death CAUTION is used to identify unsafe practices which would result in minor personal injury or product and property damage WARNING UNIT OPERATION AND SAFETY HAZARD Failure to follow this caution could result in personal injury or possible equipment damage Puron R 410A systems operate at higher pressures than R 22 systems Do not use R 22 service equipment or components on R 410A equipment Ensure service equipment is rated for R 410A INTRODUCTION The F series fan coil units are designed for flexibility in a variety of applications meeting upflow horizontal or downflow requirements Units are available in 1 1 2 through 5 ton nominal cooling capacities Factory authorized field installed electric heater packages are available in 3 through 30 kilowatts WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or possible equipment damage Before installing or servicing fan coil always turn off all power to unit There may be more than 1 disconnect switch Turn off accessory heater power if applicable UNIT IDENTIFICATION The 16 position numbering chart allows identification of all available fan coil units See Fig 2 FAN COIL DESCRIPTION AND TROUBLESHOOTING FK4B The FK4B has an integrated control and motor ECM ECM ICM and special circuit board Setting up desired airflow on the FK4B is obtained by the selections made on Easy Select circuit board The motor deliver
66. allow compressor to pump into a vacuum e Turn off electrical supply to outdoor unit f Front seat vapor service valve g Recover any remaining refrigerant NOTE All outdoor unit coils will hold only factory supplied amount of refrigerant Excess refrigerant such as in long line applications may cause compressor internal pressure relief valve to open indicated by sudden rise in vapor pressure before vapor pressure reaches 5 psig 35kPa If this occurs turn off electrical supply to outdoor unit immediately front seat vapor service valve and recover any remaining refrigerant 2 Turn off electrical supply to indoor unit 3 Disconnect condensate drain tube 4 Disconnect liquid and vapor tubes from indoor coil Use either a tubing cutter to cut tubes or a torch to unbraze tubes as required NOTE If a torch is used to unbraze line set protect fitting panel with a wet cloth or braze shield as necessary System contains oil vapors which may ignite when exposed to a flame 62 10 11 12 13 Remove coil access and fitting panels Remove screw securing coil to unit casing 5 6 thes 8 9 Remove coil pan assembly from unit Place assembly on a flat surface Remove 2 screws securing coil support columns to pan See Fig 44 Rotate columns 90 pull away from coil and remove columns from assembly Remove remaining 2 screws securing coil to condensate pan Remove coil from condensate pan Remove c
67. alve The refrigerant flow is effectively stabilized to load demand with negligible change in superheat The bi flow is used on split system heat pumps In cooling mode TXV operates the same as a standard TXV previously explained However when system is switched to heating mode of operation refrigerant flow is reversed The bi flow TXV has an additional internal check valve and tubing These additions allow refrigerant to bypass TXV when refrigerant flow is reversed with only a 1 to 2 psig pressure drop through device When heat pump switches to defrost mode refrigerant flows through a completely open not throttled TXV The bulb senses the residual heat of outlet tube of coil that had been operating in heating mode about 85 F and 155 psig This temporary not throttled valve decreases indoor pressure drop which in turn increases refrigerant flow rate decreases overall defrost time and enhances defrost efficiency PROCEDURE 1 PROBLEMS AFFECTING TXV A Low Suction Pressure 1 Restriction in TXV 2 Low refrigerant charge 3 Low indoor load 4 Low evaporator airflow B High Suction Pressure 1 Overcharging 2 Sensing bulb not secure to vapor tube 3 High indoor load 4 Large evaporator face area When installing or removing TXV wrap TXV with a wet cloth When reattaching TXV make sure sensing bulb is in good thermal contact with suction tube PISTON BODY CLEANING OR REPLACEMENT A CAUTION Do not vent refrigerant t
68. always turn on the first stage through the diodes even if the tabs are broken off E is used to turn on the third stage of electric heat Note that the W3 and E tab must be broken for this individual staging Energizing E will always turn on the first stage through the diodes even if the tab is broken off L is used as a junction to wire a diagnostic light LED on selected thermostats ransformer The proper wiring of the transformer on the HK61GA001 board is illustrated in Fig 34 Note that T2 and are wired to the primary or high side of the transformer The blue wire is connected to T3 for 208 v applications The red wire is connected to T3 for 230 v applications Units are factory wired at 230v The T2 terminal is a dummy C Indoor Fan 1 2 Wiring The fan connects to F1 F2 F3 and F4 as shown in Fig 34 Note that F2 and F3 are dummy terminals The desired fan speed is connected to F4 and the common is connected to F1 Units are factory wired at medium speed Functional Control cm QFU5 O OFU3 O 156 155 HTR5 o O YEL 154 HTR4 o BLK 424 K LK SEQ T 91 YEL LS5 HTR5 BI o O L 132 O 151 D O 2 BLK BLK aKo SEQ2 LK BLK 1 BLK BLK 4H LOW VOLTAGE Au TERMINAL BOARD BLK 1
69. apacitor and relay must be installed on single phase reciprocating compressors to boost torque to compressor motor so it may overcome the unequalized system pressures The standard is a bi flow metering device that is used in condensing and heat pump systems to adjust to changing load conditions by maintaining a preset superheat temperature at outlet of evaporator coil The volume of refrigerant metered through valve seat is dependent upon the following 1 Superheat temperature sensed by sensing bulb on suction tube at outlet of evaporator coil As long as this bulb contains some liquid refrigerant this temperature is converted into pressure pushing downward on the diaphragm which opens the valve via push rods 2 The suction pressure at outlet of evaporator coil is transferred via the external equalizer tube to underside of diaphragm 3 The needle valve on pin carrier is spring loaded which also exerts pressure on underside of diaphragm via push rods which closes valve Therefore bulb pressure equals evaporator pressure at outlet of coil plus spring pressure If load increases temperature increases at bulb which increases pressure on topside of diaphragm which pushes pin carrier away from seal opening valve and increasing flow of refrigerant The increased refrigerant flow causes increased leaving evaporator pressure which is transferred via the equalizer tube to underside of diaphragm with which the pin carrier spring pressure closes v
70. at stops calling for electric heat the signals to sequencers 1 3 are turned off and the sequencers open This causes the electric heat to turn off with the fan if the thermostat is not calling for the fan E Accessories HK61GA001 003 1 and EAC2 for Electronic Air Cleaners a There are 240 electronic air cleaner contacts provided at and EAC2 The electronic air cleaner is connected in parallel with the fan so that it is on whenever the fan is on 120 v installation is similar in function but connected between EAC2 and neutral of 230 120 v transformer connected to and EAC2 Refer to electronic air cleaner literature for further information 2 AUXI and AUX2 for 2 Speed Fan Relay Kit a Use to control fan speed operation high speed for cooling heat pump and fan only modes Low speed is used for electric heat Fig 35 shows proper connection for 24 v dc 2 speed fan relay kit Note that kit s relay coil is in parallel with fan relay coil on PCB connected to AUX1 and AUX2 Make sure the normally closed contact is connected to the lower speed b The latent capacity control kit is used to control fan speed operation when the relative humidity is above a set point on humidistat Humidistat opens and 2 speed fan relay remains in normally closed position with fan motor running at a lower speed for maximum humidity control Fig 36 shows proper connection for latent capacity control kit Note that it is connect
71. ause 24 relays may not be readily available to installer a kit exists KFAIRO101ACR containing a 24 relay which mounts directly inside EAC cabinet User supplied 110 vac is switched by relay to power air cleaner when G or W are present See Fig 8 MOUNT FLUSH WITH THESE TWO EDGES 93216 Fig 8 Mounting KFAIRO101ACR Relay Kit In heat pump applications the G signal is present in both cooling and heating modes permitting EAC to be controlled from G signal only For this application a user supplied 24 vac relay can be driven by G terminal eliminating need for relay kit B De Humidify Mode NOTE Humidistat must open on humidity rise Latent capacities for systems using Fan Coil are better than average systems If increased latent capacity is an application requirement the can be wired to provide this requirement by adjusting its airflow in response to standard humidistat input Fig 9 illustrates the wiring connections to activate de humidify mode Carefully consult product airflow data for cooling and dehumidifying mode HUMIDISTAT RED WIRE FROM ICM2 A TO PCB TERMINAL MOTOR MARKED RED HUMIDISTAT WIRING FOR DE HUMIDIFY MODE A93215 Fig 9 Humidistat Wiring for De Humidify Mode FV4B FK4D FK4C FV4A AND 40FKA The FK4C fan coil was introduced several years before the FV4A and 40FKA models All three units contain the motor and use the same control board The 40FKA
72. ccessory heater power if applicable PROCEDURE 1 FAN MOTOR The motor is 2 speed direct drive High speed lead is black low speed lead is red and common lead is yellow NOTE Unused fan speed leads must be tapped off to prevent direct short to cabinet surface The motor is turned on through 2 different routes The first occurs when thermostat calls for the fan in cooling heat pump or fan only mode A 24 vac signal is sent to relay causing relay to close its normally open contacts turning fan on The second occurs when there is a call for electric heat A 24 vac signal is sent to heater sequencer causing it to close directing 230v through the normally closed contact of fan relay turning fan on The fan remains on until sequencer opens Refer to FD3A typical wiring diagram See Fig 23 PROCEDURE 2 ELECTRIC HEATER SERVICE Service can be completed with heater in place Shut off power before servicing A Limit Switch Refer to Electric Heater Function and Troubleshooting section of this manual B Sequencer Refer to Electric Heater Function and Troubleshooting section of this manual C Transformer 60 VA transformer supplies 24 v power for control circuit Check for 208 230 v on primary side of transformer If present check for 24 v on secondary side Replace transformer if faulty NOTE Transformer is fused Do not short circuit 39 gt 0 lt SCHEMATIC DIAGRAM SEENOTERA _ au T FIELD POWER SU
73. checked Clean drain pan and condensate drain by removing any foreign matter from pan Flush pan and drain tube with clear water If drain tube is restricted it can generally be cleared by high pressure water Cut plastic line and work outside condensate pan and away from coil to clean drain tube A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Do not use caustic household drain cleaners in the condensate pan or near the coil Drain cleaners can quickly destroy a coil PROCEDURE 3 BLOWER MOTOR AND WHEEL Clean blower motor and wheel when cooling coil is cleaned WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect electrical power before removing any access panels To clean blower motor or blower wheel 1 Remove blower access panel 2 Remove motor leads from PCB Note lead location for ease of reassembly 3 Remove 2 outside screws holding blower motor assembly against blower deck flange and slide assembly out of cabinet 4 Remove screw in strap holding motor capacitor to blower housing and slide capacitor out from under strap Remove screw with green wire from blower housing Mark blower wheel motor and motor support in relation to blower housing before disassembly to ensure proper reassembly Note position of blades on wheel Loosen setscrew holding blower wheel onto motor shaft 6 Remove 3 bolts holdi
74. cordandce with NEC andlocalcodes eee FIELD POWER WIRING TRAN TRANSFORMER 5 If any of the original wire as supplied must be replaced use the same or TUE PLUG RECEPTACLE GND EQUIPMENT GROUND 6 Replace low voltage fuse with no greater than 5 amp fuse PCB BREAKOFF JUMPER RECP 7 Fuse is wired in series between transformer SEC2 and low voltage circuit AUX AUXILIARY 8 20KW heater uses one double pole LS on middle top element PCB PRINTED CIRCUIT BOARD CB CIRCUIT BREAKER 9 18 24 and 30KW heaters use double pole limit switches HPTB HEAT PUMP TERM BRD LOW VOLTAGE FUSE 10 Largest der cin are shown smaller heaters will have fewer elements and LVTB LOW VOLT TERM BRD components 11 1 phase heaters are shown wired for single supply circuit Multiple bun cee supply circuits may be wired directly to fuse C B S HVTB HIGH VOLTAGE TERMINAL BOX HUM HUMIDIFIER A94078 Table 4 Motor Conirol Test Values With 16 pin connector at motor unplugged Terminals Jumpered Volt Meter on 16 PIN Volt Meter on 7 pin Voltage EE a Select Board to WI W2 2 Verify that there are approximately 230v at terminals M1 and M2 If not determine if high voltage is entering board It enters through black and yellow wires at pins 7 and 9 in 12 pin plug 3 Verify that there is a low voltage control signal to motor The motor receives its control signals through the 7 pin motor plug P2 The voltage output
75. ctions and will display Status code 16 on the amber STATUS LED see section E Emergency Heating and Cooling Modes No further fan coil troubleshooting information will be available at the User Interface until communications are reestablished Check system wiring to be sure the User Interface is powered and connections are made A to A B to B etc and wiring is not shorted Mis wiring or shorting of the ABCD communications wiring will not allow successful communications Correcting wiring faults will clear the code and reestablish communications Shorting or mis wiring the low voltage system wiring will not cause damage to fan coil control or to User Interface but may cause the low voltage fuse to open STATUS CODE 46 BROWNOUT CONDITION If the secondary voltage of the transformer falls below 15 vac for a period exceeding 4 seconds Status Code 46 will be displayed on STATUS LED If system includes a non communicating outdoor air conditioner or heat pump the User Interface will command the fan coil to turn off Y output controlling compressor When secondary voltage rises above 17 vac for more than 4 seconds the brownout condition is cleared and normal system operation will resume subject to any minimum compressor off delay function which may be in effect Brownout does not affect blower or electric heater operation STATUS CODE 53 OUTDOOR AIR TEMPERATURE SENSOR FAULT If an OAT sensor is found at power up input is constantly checked to be wit
76. ctrical supply to indoor unit 3 Disconnect condensate drain tube 4 Disconnect liquid and vapor tubes from indoor coil Use a tubing cutter to cut tubes NOTE If a torch is used to unbraze tube set protect fitting panel with a wet cloth or braze shield as necessary tA 12 13 14 HORIZONTAL CONDENSATE PAN EXPANSION DEVICE TXV SHOWN HORIZONTAL COIL TOP SEAL DELTA PLATE VERTICAL CONDENSATE COIL BRACKET PAN SCREWS pei TA PLATE PAN 4 PER UNIT A90268 43 Component Location Remove coil access panel Remove clip securing fitting panel to condensate drain pan Remove fitting panel Remove any shipping clips including horizontal pan clip and slide coil condensate pan assembly out of unit Upflow or Horizontal Applications Only Remove horizontal condensate drain pan from coil condensate pan assembly See Fig 43 Remove 4 coil brackets See Fig 43 10 11 Remove screws at delta plates and remove coil from vertical condensate drain pan See Fig 43 Horizontal Applications Only Remove coil top seal attached with 4 screws and J shaped tube from original coil and install it in same position on new coil See Fig 43 Place coil assembly in plastic condensate pan and secure using 4 screws through delta plate See Fig 43 Horizontal and Upflow Applications Only Attach 4 coil brackets to coil pan as
77. d by a board mounted 5 amp automotive type fuse placed in series with transformer SEC2 and R circuit The C circuit of transformer is referenced to chassis ground through a printed circuit run at 5 connected to metal standoff marked GROUND SCREW REQUIRED NOTE A ground screw must be in place or erratic motor operation can result K Transformer Motor and Electric Heater Power Connections The high voltage 230 vac power input to board is provided through electric heater connector pins 7 and 9 The high voltage is then connected through printed circuit runs to motor power connections and M2 and transformer power connections and T3 Transformer connection T2 is a dummy terminal used for unused primary power lead The transformer secondary connections are made at 5 and SEC2 connectors 6 Table 3 Connections and Connector Type Type Pin No Description Heater 12 Pin Connection Motor 7 Pin Header Thermostat Y1 signal PROCEDURE 4 EASY SELECT CONFIGURATION TAPS FK4B The Easy Select taps are used by installer to configure system The motor uses selected taps to modify its operation to a pre programmed table of airflows Airflows are based on system size or mode of operation and those airflows are modified in response to other inputs such as the need for de humidification See Fig 4 The FK4B Fan Coil must be configured to operate properly with system components with w
78. damage Never operate unit without a filter or with filter access door removed Damage to blower motor may result B Coil Drain Pan and Condensate Drain WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect electrical power before removing any access panels or electrical shock may result The coil is easily cleaned when dry To check or clean coil remove coil access panel If coil is coated with dirt or lint vacuum with a soft brush attachment Be careful not to bend fins If coil is coated with oil or grease it may be cleaned with mild detergent and water solution Rinse coil with clean water Be careful not to splash water on insulation or filter Check drain pan and condensate drain at same time cooling coil is checked Clean drain pan and condensate drain by removing any foreign matter from pan Check for rust and holes Flush pan and drain tube with clear water If drain is restricted clean with high pressure water If this does not work use a plumber s snake or similar probe device Repitch drain pan to promote proper drainage FA4 FC4 4 SMART HEAT CIRCUIT BOARD FUNCTION AND TROUBLESHOOTING PROCEDURE 1 COMPONENT LAYOUT DESCRIPTION AND FUNCTION NOTE All voltages are AC unless otherwise specified 1 The low voltage terminal board is used to connect indoor thermostat to low 24 v side of transformer and to serve as a junction between indo
79. e fuse with no greater than 5 amp fuse 5 Use 60 amp class K fuses only for replacement CFM MOTORSPEEDSELECTION _____ 6 3 speed motor shown optional 2 speed motor uses BLK and LOW BLU or RED FAN COIL SIZE 018 024 030 036 042 048 060 070 7 Connect R to G to G etc see outdoor instruction for details MOTOR SPEED 24KW 8 If wire crimp is removed an emergency heat relay is required see outdoor thermostat instructions 324994 101 REV VOTORSPEEDAT30KW LO LOJLO Fig 31 Wiring Diagram of 6 Element Relay Heater C If Transformer Fuse Keeps Blowing A00173 When low voltage fuse blows it means transformer would have blown if fuse had not been in circuit to protect it The fuse usually blows when there is a high current draw on transformer high voltage applied to low voltage circuit or a direct secondary short When there is a high current draw on transformer it is most likely because transformer has been shorted or system is trying to draw more VA than transformer rating allows When fuse blows because of high voltage the system has mixed high and low voltage signals 1 Check wiring of sequencers relays as shown in Fig 30 and 29 Be sure transformer is not shorting out because thermostat wires are miswired 2 Check wiring of sequencers relays as shown in Fig 30 and 29 Be sure low voltage and high voltag
80. e level of comfort and efficiency expected by the consumer and should only be activated when User Interface cannot be replaced immediately PROCEDURE 3 FE4A FAN COIL SEQUENCE OF OPERATION The FE4A fan coil is designed for installation with a communicating User Interface This fan coil will not respond to commands provided by a common thermostat except under certain emergency situations described in Procedure 9 Start Up and Troubleshooting The User Interface uses temperature humidity and other data supplied from indoor and outdoor system components to control heating or cooling system for optimum comfort The fan coil will be commanded by User Interface to supply airflow and in the case of a non communicating outdoor unit Air Conditioner or Heat Pump control The fan coil will operate blower at requested airflow for most modes The nominal requested airflow will be 350 cfm per ton of nominal cooling capacity as defined by outdoor unit size Actual airflow request will be adjusted from nominal using indoor and outdoor temperature and indoor humidity data to optimize the system operation for occupant comfort and system efficiency Refer to User Interface literature for further system control details FE4 ADVANCED TROUBLESHOOTING Further diagnostics can be done by following the flow chart shown in Fig 18 Voltages can be measured at the communication bus with the voltages show in Table 9 CARE AND MAINTENANCE To continue high performance
81. e wiring is correct 3 Check VA draw on transformer If VA draw is more than VA rating of transformer fuse will blow If this is the case replace transformer with one that has a higher VA rating and meets system specifications D If Fan Runs Continuously 1 If PCB has no low voltage power check blue and black fan leads These may be switched at sequencer relay 2 If PCB has low voltage power check fan relay to see if it is opening and closing It may be stuck in the normally closed position due to debris in relay E Transformer Failure 1 Check 208 v and 230 v transformer connections They may be miswired HK61GA001 AND HK61GA003 CIRCUIT BOARD FUNCTION amp TROUBLESHOOTING This section of the service manual describes the HK61GA001 and HK61GA003 printed circuit boards PCB by examining the functional operation of the printed circuit board s components 1 PCB COMPONENT LAYOUT AND DESCRIPTION PROCEDURE Layout of the actual printed circuit boards are depicted in Fig 32 and Fig 33 HK61GA001 LOW VOLTAGE TERMINAL BOARD 0 be o 2ND STAGE ELECTRIC HEAT BREAKOFF TABS 9 FOR STAGING NOT USED 2FC 1 HK61GA001A PENNE
82. eck shorted element If element is shorted replace heater C No Heat 1 Check fuse for failure If fuse has failed refer to Fuse Failure section 2 Check for faulty transformer Check output voltage of transformer secondary side R red and C brown Make sure output is between 18 and 30 vac If output voltage is low and input voltage tests normal replace transformer 3 Check for miswired heater plug harness 4 Check limit switch or sequencer failure These switches should have failed in open position If output voltage is zero volts replace switch 5 Check heater relay and PCB KFC and heaters only Control voltage input to PCB should be 24 vac Output to relay should be 18 minimum If input is present but no output replace PCB If output is present replace relay gt D Heater Will Not Turn Off 1 Check low voltage wiring for miswire 2 Check for shorted elements to ground 3 Replace sequencer relays They may be stuck closed E Nuisance Trips 1 Check for low airflow due to dirty filters blocked registers or undersized duct 2 Check blower motor and wheel for proper operation Excessive current draw of motor will cause internal overload to trip 3 The fan speed may be low THERMOSTATIC EXPANSION VALVES TXV The FC4 FK4 FX4 FV4 and 40FK Fan Coils are factory equipped with a hard shutoff HSO TXV The hard shutoff TXV has no bleed port and allows no bleed through after system is shutdown A start c
83. ed in the same manner as 2 speed fan relay kit but with relay connected to humidistat orange wires c Time delay off relay kit is used to increase the efficiency of the system by delaying the fan from turning off after the thermostat is satisfied on the HK61GA001 board HK61GA003 board has this feature as standard The proper wiring and mounting of the time delay off relay kit is shown in Fig 37 d Latent capacity control and time delay off connections are shown in Fig 38 for the HK61GA001 board only PROCEDURE 3 TROUBLESHOOTING THE PRINTED CIRCUIT BOARD HK61GA001 003 Use Fig 39 wiring schematic as a guide in troubleshooting the PCB unless otherwise noted If the fan will not turn on from the thermostat IF THERE IS NO HIGH VOLTAGE TO THE PCB 1 Check the plug receptacle connection this brings power to the PCB Make sure the plug is connected properly 2 Check sequencer number 1 and the plug s wiring the yellow wire should be connected to pin number 9 of the plug and the limit switch A black wire should be connected to pin number 7 of the plug and to sequencer number 1 3 Check power leads L1 and L2 If these are not receiving power the system cannot function IF THE PCB HAS HIGH VOLTAGE APPLIED TO IT 1 Check the low voltage transformer leads R and C Make sure they are wired to the correct locations Note that Fig 39 shows wiring of the HK61GA001 board 49 8 0 6 89890
84. er elements In this situation PTCs are different in each sequencer to provide a staged ON of a minimum of 10 sec between each sequencer 3 stages of 2 elements since the KFA and KFB series heaters use sequencers in which both switches of the 2 pole sequencer close simultaneously Older models used sequencers which had a minimum delay of 10 sec between each switch Application of these devices is such that the first switch ON not only turns on first heater element but also ensures that indoor fan is energized because first ON is last OFF This ensures fan remains ON until the last heater de energizes C KFC and KFD Electric Heat Relay KFC and KFD electric heater packages have relays controlling the heater elements instead of sequencers A small rectifier PCB is mounted to each relay which converts the incoming 24 vac control signal to dc In addition to the rectifier circuit the second and third stage relays contain a time on delay circuit of 5 seconds for second stage and 8 seconds for third stage When the control signal is removed from the relays all relays will open with no time off delay PROCEDURE 2 TROUBLESHOOTING KFA KFB KFC AND KFD SERIES ELECTRIC HEATERS Discolored Wire Insulation at Terminal Check quick connect terminal at discoloration Connection may be loose creating a high resistance through connection point B Fuse Failure 1 Check for shorted wire Replace wire Never try to fix wire using electrical tape 2 Ch
85. ervice pressure rating Leak detectors should be designed to detect HFC refrigerant e Puron R 410A as other HFC s is only compatible with POE oils Vacuum pumps will not remove moisture from oil Do not use liquid line filter driers with rated working pressures less than 600 psig Do not install a suction line filter drier in liquid line POE oils absorb moisture rapidly Do not expose oil to atmosphere Wrap all filter driers and service valves with wet cloth when brazing A liquid line filter drier is required on every unit Indoor unit is equipped with a TXV Replacement TXV must be designed for Puron R 410A Do not use an R 22 TXV Never open system to atmosphere while it is under a vacuum When system must be opened for service break vacuum with dry nitrogen and replace filter driers Do not vent Puron R 410A into the atmosphere Do not use capillary tube indoor coils Observe all warnings cautions and bold text 2005 CAC BDP 7310 W Morris St Indianapolis IN 46231 65 64 Catalog No 4 6
86. es contactor in heat pump and starts compressor There is a 3 to 5 sec delay in output of Y signal At the same time control energizes fan coil s fan motor on high speed through terminals F1 and HI The LED indicator on control signals 5 flashes indicating cooling operation The call for cooling signals can be confirmed by placing voltmeter leads across low voltage terminals Y O Y 24v If 24v is not available check the following and C The reading should be o s 24v available across R and C See Ready To Start section for items to check if 24v is not available s thermostat function switch set in COOL position with thermostat calling for cooling Assuming heat pump has power and is adequately charged it should be running at this time in cooling mode Indoor fan should also be running at this time If indoor fan is not running refer to Continuous Fan section for items to check 40 D Heating Compressor Only On a call for heat room thermostat provides an input signal to control board at terminal Y This signal causes the microprocessor to provide a 24 v output signal at terminal Y to energize contactor in heat pump There is a 3 to 5 sec delay in output of Y signal Thirty sec after Y is energized control energizes fan motor It may run on high or low speed depending on its operation in previous cycle Compressor operation in current cycle is monitored by the smart control to determine whether a fan speed change
87. f motor deriving the name ECM ICM See Fig 3 An is first fed high voltage AC power through the 5 pin connector The AC power is then rectified to DC by a diode module After rectification DC signal is electronically communicated and fed in sequential order to 3 stator windings The frequency of communication pulses determines motor speed The rotor is permanently magnetized An ECM ICM is powered with high voltage at all times The motor will not run with high voltage alone Low voltage must be applied to control plug to run motor PROCEDURE 2 PCB LAYOUT AND DESCRIPTION FK4B NOTE Layout of actual PCB is depicted in Fig 4 and 5 The control is a single PCB which interfaces a variable speed motor with other system components Power for system is supplied from a 230 vac 60 Hz line Class 2 voltage 24 vac nom used for thermostat connections is derived from a transformer located in close proximity to control The primary and secondary of transformer are connected to control board The 24 vac secondary circuit includes a socket soldered into circuit at SEC2 to receive a 5 amp automotive type fuse uejs s uonisoq 9 4 1186 010 pJepuelg X 900 VOLP Y WOI ULL UOL ON WOI M 10H 5 ezis
88. fect of JW1 on Emergency Heat 3 elements 66 7 not cut 3 elements 100 100 If electric heaters were not energized prior to defrost smart control energizes sufficient elements to temper air If heaters were energized prior to defrost additional heaters will be cycled on to provide additional heat Outdoor thermostat opens A defrost initiation signal can be confirmed by attaching voltmeter leads across low voltage terminals W2D and C If 24v is not observed check the following Is 24v available across and See Ready To Start section for items to check if 24 is not available Is there continuity in thermostat leads between heat pump and smart control Is defrost control in heat pump operating properly CES013003 00 AND 01 HK61EA002 CIRCUIT BOARD FUNCTION amp TROUBLESHOOTING FA4A FB4A FC4B FF1D FH4A AND FX4A This section of the service manual describes the CESO130003 00 and 01 PCB by examining the functional operation of the PCB components PROCEDURE 1 CIRCUIT BOARD PCB COMPONENT LAYOUT AND DESCRIPTION Layout of the actual PCB is depicted in Fig 29 1 The low voltage stripped leads are used to connect the 24 v side of transformer to indoor thermostat and outdoor section 2 A 5 amp fuse is used to protect the low voltage transformer secondary 3 The fan relay is controlled by thermostat and turns fan on and off 4 A plug is used as the connection for P
89. g will not cause damage to fan coil control or to motor control module If the MOTOR LED is off STATUS LED is indicating a Status Code 44 and motor is running 1 Disconnect the motor harness at the fan coil control If motor continues to run fan coil control is good and control module on motor may need replacement STATUS CODE 25 INVALID MOTOR MODEL SELECTION On initial start up fan coil control shall poll motor for its size data and check fan coil size data stored in fan coil control memory 1 If motor size is incorrect for fan coil size or fan coil size data is invalid Status Code 25 will be displayed on STATUS LED 2 If model size data is missing as is the case when a replacement fan coil control is installed system User Interface will prompt installer to enter correct model size from a list of valid sizes 3 If motor size is incorrect for model size motor must be replaced with proper size motor Fan coil control will not respond to operation requests until this fault condition is resolved STATUS CODE 27 INVALID OUTDOOR UNIT SIZE On initial power up fan coil control will write into memory outdoor unit size as provided by User Interface in a fully communicating system 1 If outdoor unit size is invalid Status Code 27 will be displayed on STATUS LED 2 User Interface will prompt the installer to choose size from a list of valid sizes for application with fan coil 3 Check communications wiring to be sure User Interface has es
90. heavy Support panel when lowering to clean unit to avoid personal injury A WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect electrical power to all circuits before servicing unit Failure to do so may result in personal injury from electrical shock or moving parts WARNING CUT HAZARD Failure to follow this warning could result in personal injury As with any mechanical equipment personal injury can result from sharp metal edges Be careful when removing parts The minimum maintenance requirements for this equipment are as follows 1 Inspect and clean or replace field supplied air filter each month or as required 2 Inspect cooling coil drain pan and condensate drain each cooling season for cleanliness Clean as necessary To be performed by trained personnel 3 Inspect blower motor and wheel for cleanliness each heating and cooling season Clean as necessary 4 Inspect electrical connections for tightness and controls for proper operation each heating and cooling season Service as necessary NOTE Never operate without a filter or with hinged access door open Damage to blower motor may result A Cooling Coil Drain Pan and Condensaie Drain Remember to disconnect electrical power before opening hinged access panel The cooling coil is easily cleaned when dry Inspect coil and clean if necessary before each cooling season If coil inlet face is coated with dirt
91. hich it is installed To successfully configure a basic system see information printed on circuit board located next to select pins move the 5 select wires to pins which match components used A Auxiliary Heat Range The installer must select the auxiliary heat airflow approved for application with kw size heater installed If no heater is installed skip this step Each select pin is marked with a range of heaters for which airflow also marked is approved For increased comfort select the narrowest kw range matching the heater size for example 0 10 for a 10 kw heater This airflow must be greater than the minimum CFM for electric heater application with the size system installed for safe and continuous operation Note that airflow marked is the airflow which will be supplied in emergency heat mode and heating mode on air conditioners when electric heat is primary heating source To ensure safe heater operation in heat pump heating mode when electric heaters are energized the motor will run the higher of heat pump efficiency airflow and electric heater airflow The factory selection is largest heater range approved See Fig 4 AC HP Size The factory setting for air conditioner or heat pump size is largest unit meant for application with model of fan coil purchased The installer needs to select air conditioner or heat pump size to ensure that airflow delivered falls within proper range for size of unit installed in all operational modes See F
92. high voltage AC power through the 5 pin connector The AC power is then internally rectified to DC by a diode module After rectification DC signal is electronically communicated and fed in sequential order to 3 stator windings The frequency of these communication pulses determines motor speed The rotor is permanently magnetized 902 EASY SELECT BOARD TERMINAL BLOCK HUMIDISTAT Ji REMOVE 95316 Fig 15 Humidistat Wiring for De Humidify Mode ECM2 5 CONTROL POWER The ECM2 5 control power is supplied from R circuit through printed circuit runs to motor control connector Plug 1 pin 1 through motor control harness to motor The C side of low voltage control power circuit is connected by printed circuit runs to motor connector Plugl pin 2 then through motor control harness to motor A digital signal is sent from Plug 1 pins3 and 4 to communicate with the motor including all airflow requirements LOW VOLTAGE CIRCUIT FUSING AND REFERENCE The low voltage circuit is fused by a board mounted 5 amp automotive type fuse placed in series with transformer SEC2 and R circuit The C circuit of transformer is referenced to chassis ground through a printed circuit run at SECI connected to metal standoff NOTE The PCB must be mounted with 2 screws and motor ground lead secured to blower housing or erratic motor operation can result TRANSFORMER MOTOR AND ELECTRIC HEATER POWER CONNECTION Tran
93. higher VA rating and meets system specifications PROCEDURE 6 TROUBLESHOOTING FAN MOTOR A If Motor Does Not Run 1 With power turned off check all plugs and receptacles on circuit board and at motor for any deformation that may cause a bad connection Be sure all plugs are placed fully seated 8 THIS COMPARTMENT MUST CLOSED EXCEPT FOR SERVICING BLOWER MOTOR ROTATION CAUTION NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING 150V TO GROUND ATTENTION NE CONVIENT PAS AUX INSTALLATIONS DE PLUS DE 150 ALA TERRE S0KW SCHEMATIC DIAGRAM DISCONNECT PER NEC FIELD POWER WIRING SCHEMATIC DIAGRAM FIELD POWER WIRING DISCONNECT PER 6 Typical FK4B Wiring Diagram with 6 Element Heater 9 1 Beo SEERATINGPLATE L GND FOR VOLTS 8 HERTZ 1 2 o 4 i SEENOTE 1 22 SEE RATING PLATE EE Ma FOR
94. hin a valid temperature range If sensor is found to be open or shorted at any time after initial validation Status Code 53 will be displayed at amber STATUS LED Check for faults in wiring connecting sensor to OAT terminals Using an Ohmmeter check resistance of thermistor for a short or open condition If thermistor is shorted or open replace it to return the system to normal operation If fault is in the wiring connections correcting the fault will clear the code and return the system to normal operation NOTE fault condition is an open thermistor or a wiring problem that appears to be an open thermistor and the power to the fan coil control is cycled off the fault code will be cleared on the next power up but the fault will remain and system operation will not be as expected This is because on power up the fan coil control cannot discern the difference between an open sensor or if a sensor is not installed F Emergency Heating and Cooling Modes Fan coil control can provide emergency heating or cooling using a common heat cool thermostat in the event that there are no system communications fault is in User Interface and no replacement is immediately available To activate these modes the thermostat and outdoor unit must be wired as a common heating cooling system to fan coil control RYWC terminals Fan coil control must be powered and displaying Status Code 16 System Communication Fault NOTE These emergency modes do not provide th
95. ic heaters both outputs are energized and de engergized together Terminal strip inputs to control can then be connected R to W to turn on both electric heat outputs Heater output sensing circuits can then be checked to resolve Status Code 36 or 37 problems STATUS CODE 41 BLOWER MOTOR FAULT If MOTOR LED is lit and flashing and motor does not run 1 Check STATUS LED If STATUS LED is indicating Status Code 41 motor control has detected that the motor will not come up to speed within 30 seconds of being commanded to run or that the motor has been slowed to below 250 rpm for more than 10 seconds after coming up to speed Motor wiring harness and fan coil control are operating properly do not replace 2 Check to be sure that the blower wheel is not rubbing the housing 3 Check motor to be sure that the motor shaft is not seized motor control module must be removed and electronics disconnected from windings to perform this check properly 4 Check motor windings section following instructions in Section C ECM Motor Troubleshooting If all these checks are normal the motor control module may need replacement STATUS CODE 16 SYSTEM COMMUNICATION FAULT If at any time system communications are not successful for a period exceeding 2 minutes the fan coil control will only allow emergency heating or cooling operation using a common thermostat a non communicating outdoor unit and the R C Y O W outdoor unit terminal strip conne
96. ides a quick summary of how to troubleshoot the FK4B If more information is needed refer to appropriate sections of this service manual MOTOR If motor is hard to turn manually but turns freely replace module If motor does not run check the components listed below according to their instructions If motor runs in some operation modes and not in others check for a good ground connection between motor ground lead and circuit board screw marked ground screw and check the room thermostat and wiring harness according to instructions listed in Table 4 If motor does not stop running remove the 7 pin plug from circuit board If motor continues to run replace motor If motor stops running after 2 minutes it is either the circuit board or thermostat causing the problem Test whether thermostat is at fault by disconnecting it from the board CIRCUIT BOARD Check 5 amp fuse Check for 230v between terminals M1 and M2 If no voltage is present check power to board 230 v power enters the board through the black and yellow lead in the 12 pin plug Check for 24v between 5 and 5 2 If no voltage is present check the transformer Check for burn traces or burnt components If burn spots are present replace board ROOM THERMOSTAT Remove thermostat wires from the circuit board Jumper screw terminals 1 at a time R G R Y Y2 R Y1 and R W2 If motor runs in all cases thermostat or thermostat wiring is bad If
97. ig 4 C System Type The type of system must be selected 1 AC air conditioner 2 HP COMFORT provides same airflow as air conditioner selection approximately 375 CFM ton 3 HP EFF provides most efficient airflow for heating and cooling modes approximately 410 CFM ton heating and 375 CFM ton cooling The factory setting is AC See Fig 4 D CFM Adjust Select low medium or high airflow The factory selection is LO The adjust selections HI LO will regulate airflow supplied for all operational modes except non heat pump heating modes 10 percent and 10 percent respectively The adjust selection options are provided to adjust airflow supplied to meet individual installation needs for such things as noise comfort and humidity removal See Fig 4 E AC HP Time Delay Select desired time delay profile Four motor operation delay profiles are provided to customize and enhance system operation See Fig 4 The selection options are NOTE Selectable ON and OFF delay active in heat pump heating and cooling modes only Auxiliary heat modes have a fixed delay profile 0 seconds ON or 2 minutes OFF This cannot be overridden 1 The standard 90 sec off delay factory setting 2 No delay option used for servicing unit or when a thermostat is utilized to perform delay functions 3 30 sec on 90 sec off delay profile used when it is desirable to allow system coils time to heat up cool down prior to airflow This
98. ilable at control s low voltage terminal strip terminals R and C If 24v is not present across R and C check the following Is low voltage fuse on control board good e Are line voltage fuses FU1 FU2 good Is LED on control on steadily or not on at all Both of these indications signal a possible board failure Is 208 230 v power available to control across pins 7 and 9 9 pin connector Is connection to board tight B Continuous Fan On a call for continuous fan thermostat provides a 24 v input signal to G terminal on low voltage terminal strip Sensing this signal the microprocessor energizes a relay on control to provide power to high speed winding of fan motor at 1 The fan continues to run until fan switch on thermostat is turned off Table 13 Troubleshooting Voltage Readings and Test Points Input Voltages Location Normal Reading and L2 208 230 vac power supply input to fan coil L3 and L4 208 230 vac 9 pin connector 208 230 vac Power to smart control 7 and 9 1 and T3 and SEC R and C G and C Y and C O and C 24 vac Signal to energize reversing valve from room thermostat cooling Also present during defrost W2T and C Call for electric heat from room thermostat W2D and C Defrost initiation signal from heat pump Output Voltages 1 and 4 NOTE Sequencers use DC voltage 2 and 4 9 pin connector 24 vde Power to energize SEQ 3 3 and 4 vac volts AC vdc
99. ining refrigerant NOTE All outdoor unit coils will hold only factory supplied amount of refrigerant Excess refrigerant such as in long line applications may cause compressor internal pressure relief valve to open indicated by sudden rise in vapor pressure before vapor pressure reaches 5 psig 35kPa If this occurs turn off electrical supply to outdoor unit immediately front seat vapor service valve and recover any remaining refrigerant 2 Turn off electrical supply to indoor unit 3 Disconnect condensate drain tube 4 Disconnect liquid and vapor tubes from indoor coil Use a tubing cutter to cut tubes NOTE If a torch is used to unbraze tube set protect fitting panel with a wet cloth or braze shield as necessary 5 Remove coil access panel 6 Remove clip securing fitting panel to condensate drain pan Remove fitting panel 7 Remove any shipping clips including horizontal pan clip and slide coil condensate pan assembly out of unit 8 Upflow or Horizontal Applications Only Remove horizontal condensate drain pan from coil condensate pan assembly See Fig 43 9 Remove 4 coil brackets See Fig 43 10 Remove screws at delta plates and remove coil from vertical condensate drain pan See Fig 43 11 Horizontal Applications Only Remove coil top seal attached with 4 screws and J shaped tube from original coil and install it in same position on new coil See Fig 43 12 Place coil assembly in plastic condensate pa
100. is required for enhanced indoor comfort The LED indicator on control signals 1 flash indicating compressor operation only with no electric heat The call for heat signals can be confirmed by placing voltmeter leads across low voltage terminals Y Y and The readings should be 24v If 24v is not available check the following s 24v available across R and C See Ready To Start section for items to check if 24v is not available s thermostat function switch set in HEAT position with thermostat calling for heat Assuming heat pump has power and is adequately charged it should be running at this time in heating mode Indoor fan should also be running at this time If indoor fan is not running refer to Continuous Fan section for items to check When room thermostat is satisfied indoor fan continues to run an additional 60 sec to recover heat remaining in indoor coil E Heating Compressor and Electric Heat If heat pump alone cannot satisfy heat requirements of structure room thermostat calls for additional heat by way of an input to W2 terminal of control When this occurs control begins sequencing on electric heaters by energizing the first sequencer heat relay Indoor fan should be running at this time If room temperature requirements cannot be met additional stages of electric heat are energized through the other 2 sequencers relays at 2 The logic of control determines how much and how soon these additional stages are brought on
101. ist disconnect wiring harness at fan coil control heater header and check for a resistance value greater than 5000 ohms 3 Check for proper wiring of resistor assembly 4 Make sure heater size installed is an approved size for outdoor unit and fan coil sizes installed NOTE Fan coil control will not operate electric heater until this Status Code is resolved If the heater size is set through the User Interface the heater will be operated as a single stage heater If staging is desired the IDR value must be read in by the fan coil control STATUS CODE 36 HEATER OUTPUT NOT SENSED WHEN ENERGIZED Fan coil control is provided with circuitry to detect presence of a 24 vac signal on Electric Heater stage 1 and stage 2 outputs If fan coil control energizes either heater stage and does not detect the 24 vac signal on output Status Code 36 will be displayed on the STATUS LED Fan coil control will continue to energize heater output s and adjust blower operation to a safe airflow level for energized electric heat stage s To find the fault 1 Check for 24 vac on heater stage outputs Fan coil control or sensing circuit may be bad NOTE It may be useful as an electric heater troubleshooting procedure to disconnect the system communications to force Status Code 16 enabling of emergency heat mode It is difficult to know which heater output is energized or not energized in normal operation When fan coil is operated in emergency heat mode using electr
102. k low voltage signals The ECM motor in these fan coils receive low voltage signals from the Easy Select Board through the wiring harness assembly The combination of pins energized at the motor determines the speed the motor will run The procedure below isolates the fan coil from all external devices such as a thermostat condensing unit humidifier or electronic air cleaner There is also a specific troubleshooting example to demonstrate the process Table 7 provides information needed to verify that the correct voltages are present at the motor and the Easy Select Board THERMOSTAT 1 Remove all thermostat and accessory wires from Easy Select Board 2 On Easy Select Board jumper screw terminals 1 at a time R G R Y Y2 R Y1 R W1 R W2 If motor runs in all cases check thermostat outputs Thermostat wires may be broken or thermostat may be miswired configured incorrectly or defective If the motor does not run or runs in some cases but not others continue this procedure to check wiring harness and circuit board WIRING HARNESS 1 Remove 16 pin plug from motor 2 Check for appropriate voltages on 16 pin connector with screw terminals jumpered See Table 6 3 If signals check correctly and motor does not run inspect wiring harness for loose pins or damaged plastic that could cause poor connections 4 If connections are good either control module or motor is defective 5 If proper signals are not present check circuit boa
103. k with binding facing coil Press top edge under access panel NOTE Steel rods in filter prevent it from being pulled into coil Retain these rods and reinstall after cleaning or before replacement if new filter 15 used A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Never operate unit without a filter B Cooling Coil Drain Pan and Condensate Drain The cooling coil is easily cleaned when it is dry Inspect coil and clean if necessary before each cooling season To check or clean cooling coil remove blower heater access panel to gain full access to cooling coil If coil is coated with dirt or lint vacuum with a soft brush attachment Be careful not to bend coil fins If coil is coated with oil or grease clean it with a mild detergent and water solution Rinse coil with clear water Be careful not to splash water onto insulation Inspect drain pan and condensate drain at same time cooling coil is checked Clean drain pan and condensate drain by removing any foreign matter from pan Flush pan and drain tube with clear water If drain tube is restricted it can generally be cleared by high pressure water Cut plastic line and work outside condensate pan and away from coil to clear drain tube NOTE There MUST be a trap in condensate line Trap must be at least 3 in deep not higher than the bottom of unit condensate drain opening and pitched downward to an open drain or sump A CAUTION
104. led from Easy Select Board Control closes R to to Y Y2 and R to heat pump only and open to DH Dehumidification is active when 24vac is removed from DH terminal Unit delivers 20 less airflow E SuperDehumidify Mode Thermidisat or Comfort Zone II B indoor control Single Speed Outdoor Unit This mode is only activated by the indoor control when COOL to DEHUMIDIFY SUPERDEHUMIDIFY are configured at the control and there is a call for dehumidfication without a call for cooling The control closes R to Y Y2 R to O heat pump only and opens R to DH and R to G This signals the fan coil to run at minimum airflow for maximum humidity removal The control will cycle the equipment 10 minutes on and 10 minutes off until satisfied 9 TA SEC1 SEC2 5 p OM 1 CD C 2 pau 3 EASY SELECT l 5 AUXIHEAT KW CFM 0 30 0 20 0 10 0 5 1075 875 725 625 W vol SIZE LE 2 036 030 024 018 BU 4 HP EFF YN ORN CFM ADJUST zu wr Cc LO 8 BLK EJ ui ee ON OFF DELAY
105. mergency Heat Emergency heat mode requires that room thermostat be placed in EMERGENCY HEAT position This locks out and prevents operation of heat pump outdoor unit In this mode heat is provided exclusively by electrical heaters in fan coil In this mode room thermostat at 1 provides an emergency heat input signal to smart control at terminal W2T If jumper JW1 at 2 has not been cut and an outdoor thermostat installed to control electric heat stages that same input signal is applied to terminal W3 For this example assume that jumper has not been cut Eventually the total number of heaters is cycled on In emergency heat mode LED indicator signals 7 flashes The amount of emergency heat available depends on whether jumper 1 is cut and the number of heating elements Table 14 illustrates results under various conditions The heaters cycle on two elements initially and an additional element every 5 minutes until maximum level is reached With JW1 cut an outdoor thermostat if closed could cycle on additional heaters and system would perform as if 1 was not cut In effect closed outdoor thermostat replaces cut jumper H Defrost In defrost mode LED indicator signals 6 flashes Defrost is initiated by heat pump and is signalled to smart control by an input to W2D terminal During defrost outdoor unit switches to cooling mode making it necessary to cycle on electric heaters to temper indoor air 41 Table 14 Ef
106. motor does not run or runs in some cases but not in others continue by checking the wiring harness WIRING HARNESS Shut off power to unit Remove 5 pin plug from motor A WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or possible equipment damage Never remove 5 pin high voltage plug from the motor with the power on Remove 16 pin plug from motor Replace 5 pin plug and turn on power 10 Check for 24v between pin 1 and 12 on 16 pin plug See Fig 7 If no voltage is present replace wiring harness If voltage is present 16 PIN PLUG A94375 Fig 7 Wiring Harness 16 Plug jumper screw terminal R Y Y2 on circuit board and check for 24v between pin 1 and pin 12 and pin 1 and pin 14 on 16 pin plug See Fig 7 If voltage is present replace harness If 24v is present on both pins the motor or module is bad Replace motor PROCEDURE 8 ACCESSORIES FK4B A Electronic Air Cleaner EAC Familiar 230 vac EAC control power signal and 2 15 not available because the motor blower motor used in the FK4B Fan Coil 15 controlled by low voltage signals This signal is replaced by 24 vdc signal which is provided at circuit board terminals AUX1 and AUX2 See Fig 16 This signal is present when either or W is present and is active in all heating and cooling modes Bec
107. n and secure using 4 screws through delta plate See Fig 43 13 Horizontal and Upflow Applications Only Attach 4 coil brackets to coil pan assembly See Fig 43 14 Horizontal Applications only Place horizontal condensate pan into position on coil pan assembly NOTE Installation of horizontal condensate pan is not necessary for upflow or downflow applications 15 Slide complete assembly into unit 16 Reinstall fitting panel and reconnect clip securing fitting panel to condensate drain pan 17 Horizontal Applications Only Reinstall horizontal pan clip Secure with 1 screw See Fig 43 Reinstall coil access panel 18 Reconnect liquid and vapor refrigerant tubes and condensate drain tube Install new Puron R 410A liquid line filter drier 19 Evacuate tube set and indoor coil to 500 microns back seat open liquid and vapor service valves 20 Turn on electrical supplies to indoor and outdoor units 21 Check system refrigerant charge and operation See Application Guideline and Service Manual for R 410A for further information PROCEDURE 2 SLOPE COIL UNITS If it is determined that system does not have leaks and refrigerant is not contaminated proceed as follows 1 Recover system refrigerant a Attach manifold gage set to service valves b Front seat close liquid tube service valve c Start unit in cooling mode d Run unit until low pressure switch opens at 50 psig 350kPa or vapor pressure reaches 5 psig 35kPa Do not
108. nd off 10 A plug is used as the connection for the PCB power and electric heaters Note the pin numbers on the plug 11 Diodes provide DC power for the fan relay and the first stage of electric heat W2 W3 or E PROCEDURE 2 PCB COMPONENT FUNCTIONS A Low Voltage Terminal Board HK61GA001 003 The low voltage terminal board connects the indoor thermostat to the outdoor unit as shown in Fig 34 The terminals are listed as follows along with their functional control 46 55 used to connect the secondary side HK61GA003 LOW VOLTAGE TERMINAL BOARD Dx 2ND STAGE ELECTRIC HEAT BREAKOFF TABS FOR STAGING FAN INTERLOCK T DIODES AND FAN 3RD STAGE TIME DELAY OFF CIRCUIT oE a o Y d 5 FUSE L LOW VOLTAGE f 5 FUSE MAX PLUG BT 0000 O 9 5 0 HK61GA003 ae 24VDC ACCESSORIES gt 2 FAN RELAY FAN CONNECTIONS TRANSFORMER a CONN
109. ng Diagram A94376 D Fan Relay Relay coil is 24 volts Check for proper control voltage Replace relay if faulty E Heater Removal Disconnect wiring remove 2 sheet metal screws and pull heater out through open hinged access panel When replacing heater ensure orientation of heater element is same as when removed PROCEDURE 3 CLEANING OR REPLACING REFRIGERANT FLOW CONTROL DEVICE 1 Pump down outdoor unit Close service valves at outdoor unit N CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Damage may occur to the scroll compressor if operated at a negative suction pressure during a system pumpdown 2 Bleed and if possible recover remaining refrigerant from tubing and coil through gage port on vapor tube service valve 3 Disconnect liquid refrigerant tube from refrigerant flow control device Refer to Fig 24 4 Remove refrigerant flow control device piston retainer Avoid damaging O ring or machined surfaces on piston bore and retainer 5 Using small wire with a hook on end of it remove piston from refrigerant flow control device body THREAD PROTECTOR RUBBER PISTON BODY O RING pe 92219 Fig 24 Refrigerant Flow Control Device For FD3A and FG3A A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage When cleaning piston orifice be careful not to scratch or enlarge opening as this will affect operation
110. ng motor mount to blower housing and slide motor and mount out of housing Further disassembly should not be necessary as adequate clearance is available 7 Remove blower wheel from housing by removing cutoff plate from blower housing outlet Note wheel orientation and cutoff location for reassembly The blower motor and wheel may be cleaned by using a vacuum with a soft brush attachment 8 Remove grease with a mild solvent such as hot water and detergent Be careful not to disturb balance weights clips on blower wheel vanes Also do not drop or bend wheel as balance will be affected 26 CAN NOT FIND INDOOR UNIT Disconnect O D unit and all other deviices on ABCD bus except indor unit and UI Cycle system power YES Reconnect one device at a time to ABCD bus Indoor unit found NO Connect UI to indoor unit Device at the indoor unit found Indoor YES unit found Check wiring to UI Check device mounting location wiring NO YES Measure voltage on ABC terminals at device see NO Possible device problem Try another UI Correct Measure voltage on ABC vitm g and terminals at indoor unit see Table 1 Possible indoor reinstall system unit problem Fig 18 FE4 Advanced Troubleshooting Flow Chart A04160 To reassemble blower 1 Place blower wheel back into housing Be sure to position correctly for proper location 2
111. o atmosphere Recover during system repair or final unit disposal N CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Damage may occur to the scroll compressor if operated at a negative suction pressure during a system pumpdown 1 Pump down outdoor unit Close service valves at outdoor unit 2 Recover remaining refrigerant from tubing and coil through gage port on vapor tube service valve Disconnect refrigerant liquid tube from piston body See Fig 42 3 Avoid damaging seal ring or machined surfaces piston bore and retainer 4 Using small wire with a hook on end of it remove piston from body TEFLON SEAL PISTON PISTON BRASS RETAINER HEX BODY BRASS HEX NUT A93530 Fig 42 Refrigerant Flow Control Device For FA FB and FF A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage When cleaning the piston orifice be careful not to scratch or enlarge the opening as this will affect operation Install new or cleaned piston into body Replace seal ring on retainer Reconnect refrigerant tube to piston body Pressurize tubing and coil then leak check tA Evacuate tubing coil as necessary A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage Use a backup wrench and do not over tighten as
112. oard Plug column and row for pin 14 on motor plug to see pin on Easy Select Board that should have voltage The correct pin is 2 The column on far right will show voltage that should be present between pin 2 and pin 9 common 3 Place meter leads between pins 2 and 9 on Easy Select Board and check for 12vdc 4 If voltage is present the wiring harness is bad If not the Easy Select Board is bad Verify Motor Winding Section Before proceeding with module replacement check the following to ensure motor winding section is functional With control module removed and unplugged from winding section 1 The resistance between any 2 motor leads should be similar 2 The resistance between any motor lead and the unpainted motor end plate should be greater than 100K ohms If motor winding fails one of these tests it is defective and must be replaced F Accessories AUXILIARY TERMINALS The AUX and HUM terminals on the Easy Select Board are tied directly to the G terminal and provide a 24 vac signal whenever the G terminal is energized See Fig 5 and Fig 6 During Superdehumidify mode the G signal is not present and the auxiliary terminals are not energized If the installation includes the use of this operating mode do not use these terminals to control accessories See Electronic Air Cleaner and Humidifier sections for further information 19 Table 8 Motor Conirol Test Values With 16 pin connector at motor un
113. odule Easy Select Board or entire motor The control module is available as a replacement part D If Motor Turns Slowly 1 It is normal operation to run noticeably slower if G terminal is not energized in cooling or heat pump heating modes 2 Attach blower access panel Motor may appear to run slowly if access panel is removed E If Motor Does Not Run Turn power off wait 5 minutes and check the following 1 With power turned off check 5 amp fuse on Easy Select Board 2 Check all plugs and receptacles for any deformation or corrosion that could cause bad connections Be sure plugs are fully seated N CAUTION ELECTRICAL OPERATION HAZARD Failure to follow this caution may result in equipment damage or improper operation DO NOT remove or apply 5 pin plug on motor with power on Arcing could occur which can damage control module zy THIS COMPARTMENT MUST BE CLOSED EXCEPT FOR SERVICING BLOWER MOTOR ROTATI ON 20KW SCHEMATIC DIAGRAM FIELD POWER WIRING SEE RATING PLATE DISCONNECT PER NEC FOR VOLTS amp HERTZ T SEE NOTE 1 poa 1 2 e 2 E 4 4 INTERNAL PROTECTION MAY 1 BE EITHER FUSES OR CIRCUIT Q BREAKERS Q BLK RELAY 2 SECI SEC2
114. of each pin in plug will be different for each mode of operation Table 4 lists circuit board screw terminals that have 24 vac present powered by thermostat and lists voltage that is present at each pin of 7 pin plug for each operating mode Tests should be taken between points listed and common screw terminal If all values of any 1 of operating modes checks OK and motor fails to run then motor is defective and should be replaced B If Motor Does Not Run Smoothly First verify that the cause is not an out of balance or damaged blower wheel If it is not blower wheel motor is defective and should be replaced C If Motor Shaft Does Not Rotate Smoothly When manually turning shaft of ECM ICM the shaft does not rotate smoothly The shaft has steps during rotation referred to as motor cogging The cogging is caused by permanent magnets passing each pole of motor However shaft should not require excessive force to turn If shaft is VERY difficult to turn motor control or bearings have failed and motor must be replaced D If Motor Does Not Stop Running 1 Check for good ground between motor ground lead and transformer common lead 2 If motor continues to run remove all thermostat wires If motor stops check thermostat wiring for short 3 If motor continues to run remove the 7 pin plug If motor continues to run after 2 minutes replace motor PROCEDURE 7 CONDENSED VERSION OF TROUBLESHOOTING FK4B MOTOR AND CONTROLS This section prov
115. oil top seal See Fig 44 Install new coil into condensate pan using 2 original screws and 2 support columns NOTE Correct coil position in condensate pan is essential to reliable operation 14 15 16 17 18 19 Install new coil pan assembly into unit Secure with 2 screws previously removed from unit casing Reinstall coil access and fitting panels Reconnect liquid and vapor refrigerant tubes and condensate drain tube Install new Puron R 410A liquid line filter drier Evacuate tube set and indoor coil to 500 microns back seat open liquid and vapor service valves Turn on electrical supplies to indoor and outdoor units Check system refrigerant charge and operation See Application Guideline and Service Manual for R 410A for further information PURON R 410A QUICK REFERENCE GUIDE FOR INSTALLERS AND TECHNICIANS e Puron R 410A refrigerant operates at 50 70 percent higher pressures than R 22 Be sure that servicing equipment and replacement components are designed to operate with Puron R 410A R 410A refrigerant cylinders are rose colored e Recovery cylinder service pressure rating must be 400 psig DOT 4 400 or DOT BW400 e Puron R 410A systems should be charged with liquid refrigerant Use commercial type metering device in the manifold hose e Manifold sets should be at least 750 psig high side and 200 psig low side with 520 psig low side retard Use hoses with 750 psig s
116. or W input E Heat Pump Heating Mode Single Speed or 2 Speed High Thermostat closes circuit R to Y Y2 for single speed A circuit from R to Y1 is also required for 2 speed high The Y Y2 signal is sent directly to motor F Heat Pump Heating Mode Two Speed Low Thermostat closes R to Y1 The Y1 signal is sent directly to motor 5 Table 1 Male Female Quick Connect Terminals FK4B Description 0 250 X 0 032 Motor line voltage connection 230 vac 60 Hz Transformer line voltage connection 230 vac 60 Hz Transformer tap storage terminal for 208 vac lead Secondary connection from transformer 24 vac This connection is common to chassis ground through eyelet marked GROUND SCREW REQUIRED Secondary connection from transformer 24 vac Low voltage ground for humidifier option 24 vdc Low voltage output for humidifier option 24 vdc Low voltage ground for auxiliary option 24 vdc Low voltage output for auxiliary option 24 vdc 0 187 X 0 032 Common connection to blower motor PER Common connection for transformer Common to R screw terminal and SEC2 Table 2 Connections on FK4B Screw Terminal Block Screw Description Terminal Connection for G signal from thermostat Connection for O signal from thermostat L This connection is a field termination for use in connecting L lines of thermostat and outdoor unit to gether There is no connection of this terminal with control circuity Connection fo
117. or thermostat and outdoor section CEPL130121 01 MOV1 LOW VOLTAGE TERMINAL BOARD CESS430121 01A CUT WHEN OUTDOOR THERMOSTAT IS USED HIGH FAN ONLY WHEN CUT RECEPTACLE LIP JUMPER FOR HIGH FAN ONLY CES0130025 4 94127 2 Fig 27 Smart Heat Printed Circuit Board PCB R terminal is used to connect secondary side of transformer to thermostat and outdoor unit R is fused terminal is used to connect transformer secondary common for thermostat and outdoor unit Y terminal provides input signal from thermostat signaling heat pump operation G terminal provides input signal from thermostat signaling continuous fan operation O terminal provides input and junction terminal for reversing valve signal m W2D terminal provides input from outdoor unit heat pump signaling control board that heat pump is in defrost W2T terminal provides input from thermostat signaling for supplemental or emergency heat 99 Ex terminal provides input from outdoor thermostat W3 and W2T are factory connected by JW1 This input is used only if an outdoor thermostat is required by local codes Y terminal provides output from control board to energize
118. ormer cannot supply power to board with fuse blown or loose If fuse blows when unit has power applied to it the system most likely has 1 of the following problems a Check control circuit for a short or miswiring problem b The maximum load on transformer is 40 VA If load on transformer is excessive the low voltage 5 amp fuse will blow to protect transformer If load exceeds VA rating of transformer a larger VA rated transformer needs to be installed Check sequencers for excessive current draw c Check wiring of heaters If a heater is miswired fuse may blow If a heater is miswired correct miswiring 4 Check T2 and T3 connections on primary side of transformer If they are not connected properly low voltage terminal board cannot supply 24 v signal to energize fan motor If transformer is receiving correct primary voltage but is not putting out correct secondary voltage transformer needs to be replaced B If Electric Heat Stages Will Not Turn On But Fan Will Turn On 1 Check wiring of sequencers Pay particular attention to high and low voltage wiring of sequencers 2 Check plug wiring to make sure that it is wired correctly 3 Check voltage to sequencer Sequencer number 1 receives a 24 vac signal If it is receiving correct voltage check to see if sequencer is closing If sequencer is not closing but is receiving correct voltage replace sequencer If sequencer is closing check high voltage wiring as discussed in items
119. ot be turned on without the fan being turned on at the same time This is a fan interlock system 2 W3 When a signal is sent to W3 2 control signals are sent out to the sequencers a 24 v dc signal to sequencer number through the diode interlock and a 24 vac signal to sequencer number 2 The 24 vac signal applied to sequence number 2 causes the sequencer to close with the second stage of electric heat turning on after a short delay The 24 v dc signal applied to sequencer number 1 causes the first stage of electric heat to turn on in the same manner as described in W2 above Note that W3 is interlocked with the fan since sequencer number is turned on whenever W3 has a signal sent to it Timing is such that sequencer number 1 will turn on before sequencer number 2 When the signal to W3 is turned off sequencer number 2 opens after a short delay If W2 is also satisfied the first stage of electric heat and the fan will also turn off providing the thermostat is not calling for the fan to be on E When the thermostat sends a signal to E 2 signals are sent out to the sequencers A 24 vac signal is sent to sequencer number 3 and a 24 v dc signal is sent to sequencer number 1 The 24 vac signal applied to sequencer number 3 turns on the third stage of electric heat The 24 v dc signal applied to sequencer 1 turns on the first stage of electric heat and the fan in the same manner as W3 Note that E is also interlocked with the fan When the thermost
120. outdoor unit heat pump contactor 2 Jumper wires JW1 and JW2 See Fig 27 a JW1 connects W2T to W3 to limit staging of electric heat with use of an outdoor thermostat See Table 11 for staging Smart Heat PCB controls staging to the extent that this feature is unnecessary unless required by local codes or regulations b Cutting JW2 sets Smart Heat PCB in efficiency mode With JW2 cut there is loss of performance due to reduced indoor blower speed when heat pump is operating near balance point This jumper may need to be cut if selected cooling fan speed is the same as required minimum motor LO speed tap selection With JW2 cut fan terminal LO becomes a dummy terminal A fuse is used to protect low voltage transformer and PCB AUX and AUX are connections for air conditioning accessories EAC humidifier etc Fl F2 and LO are connections for indoor fan The 9 receptacle connects heater package wiring harness 7 5 and SEC2 are used to connect secondary side of transformer to PCB 5 is internally connected to equipment ground PROCEDURE 2 UNIT FUNCTIONS A Transformer NOTE Terminals T2 if used and T3 are wired to primary or high side of transformer The 208 v terminal or blue wire if transformer has primary leads is used on T3 for 208 v applications The 230 v terminal or red wire is used on T3 for 230 v applications T2 is a dummy terminal B Electric Heat NOTE When
121. plete The heater sequence SEQ is energized which closes contacts of relay There will be a time delay This completed circuit energizes all heating elements HTR and blower motor B Heat Pump COOLING On a call for cooling the thermostat makes circuits R O R Y and R G Circuit R O energizes reversing valve switching it to cooling position Circuit R Y energizes contactor starting outdoor fan motor and compressor Circuit R G energizes indoor unit blower relay starting indoor blower motor When thermostat is satisfied its contacts open de energizing contactor reversing valve and blower relay This stops compressor and fan motors HEATING On a call for heating the thermostat makes circuits R Y and R G Circuit R Y energizes contactor starting outdoor fan motor and compressor Circuit R G energizes indoor blower relay starting blower motor Should temperature continue to fall R W circuit is made through second stage room thermostat bulb Circuit R W energizes a sequencer bringing on supplemental electric heat When thermostat is satisfied its contacts open de energizing contactor and sequencer All heaters and motors should stop PROCEDURE 6 CARE AND MAINTENANCE The minimum maintenance requirements for this equipment are as follows 1 Inspect and clean or replace air filter each month or as required 2 Inspect cooling coil drain pan and condensate drain each cooling season for cleanliness Clean as necessary 29 SCHEMATIC DIA
122. plugged Terminals Jumpered Volt Meter on 16 Volt Meter on 12 pin Voltage Harness Plug Easy Select Board Plug _ _ oa o __ i 24vac Pi EYRE SE cu ox AUX1 AUX2 GND NEUT A 4 4 Z x ra ra o m 24 VAC RELAY Li WHT LO 98625 Fig 14 KFAIRO201ACR Relay Kit Wiring Schematic ELECTRONIC AIR CLEANER CONNECTIONS The AUXI and AUX terminals are not always energized during blower operation as described above When using an electronic air cleaner with the FV4 fan coil use Airflow Sensor The airflow sensor turns on electronic air cleaner when the fan coil blower is operating HUMIDIFIER HUMIDISTAT CONNECTIONS Easy Select Board terminals and 2 are provided for direct connection to the low voltage control of a humidifier through a standard humidistat These terminals are energized with 24vac when G thermostat signal is present Alternately the 24 vac signal may be sourced from the and C terminal block connections when electric heaters are used as primary heating source When using a Thermidistat Control Zone Perfect Plus or Comfort Zone II the 24 vac signal may be source directly from the Thermidistat HUM terminal FK4 FV4 and 40FK Dehumidify Mode
123. pplied to control plug to run motor ECM ICM 2 CONTROL POWER The motor ECM2 control power is supplied from R circuit through printed circuit runs to motor control connector pin 8 through motor control harness to motor The C side of low voltage control power circuit is connected by printed circuit runs to motor connector pins 9 10 and 11 then through motor control harness to motor LOW VOLTAGE CIRCUIT FUSING AND REFERENCE The low voltage circuit is fused by a board mounted 5 amp automotive type fuse placed in series with transformer SEC2 and R circuit The C circuit of transformer is referenced to chassis ground through a printed circuit run at 5 connected to metal standoff marked NOTE The PCB must be mounted with 2 screws and motor ground lead secured to blower housing or erratic motor operation can result TRANSFORMER MOTOR AND ELECTRIC HEATER POWER CONNECTION Transformer high voltage supplied from electric heater package or high voltage leads through 12 pin heater connector plug recp2 The motor ECM2 power connections are made at the transformer primary terminals The transformer secondary connections are made at SEC1 and SEC2 connectors COMFORT HEAT PUMP SYSTEM In 1998 the Comfort Heat Pump System was introduced in which a 40FK FK4 FV4 fan coil can be installed This introduced many new features for enhanced comfort To activate these modes they must be configured into the indoor control The Thermidistat Control and current
124. r low speed compressor operation Connection for R signal to thermostat 24 vac Connection for C terminal to thermostat 24 vac common G Heat Pump Heating With Auxiliary Electric Heat Thermostat closes circuits R to Y Y2 and or R to Y1 with R to W2 W3 or E and R to O in the case of defrost See previously described modes for circuit paths In the event that electric heating is called for by thermostat while heat pump is also operating in either heating or defrost mode electric heating signal will appear at motor connector pin 1 as described previously If necessary the motor will modify its airflow output to provide an airflow which is defined as safe for operation of electric heater H CFM Select Configuration Taps The CFM Select taps are used by installer to configure system The motor is capable of discerning wave shapes on some of its inputs and uses this capability to modify its operation to a pre programmed table of airflows and can be modified in response to other inputs such as the need for de humidification Motor Control Power The motor control power is supplied from R circuit through printed circuit runs to motor control connector pin 6 through motor control harness to motor The C side of low voltage control power circuit is connected by printed circuit runs to motor connector pins 4 and 5 then through motor control harness to motor J Low Voltage Circuit Fusing and Reference The low voltage circuit is fuse
125. rcuit This can be prevented by making sure PCB is wired correctly before PCB has power applied to it 44 THIS COMPARTMENT MUST BE CLOSED EXCEPT FOR SERVICING BLOWER MOTOR CAUTION NOT SUITABLE FOR USE ON SYSTEMS EXCEEDING 150V TO GROUND ROTATION ATTENTION NE CONVIENT PAS AUX INSTALLATIONS DE PLUS DE 150 VALA TERRE SCHEMATIC DIAGRAM COMPONENT ARRANGEMENT FIELD POWER WIRING DISCONNECT PER NEC GED Go d ph h og i 0909 GND 9 902 1997 7 BLK BLK 156 HIRS Fue RELAY 3 SYSTEM TRANSFORMER 40 0VA 5 7 H2 BLK 1 FAN 52 HIRE uk BLK jp VA AVAILABLE 248VA RED amp 208v YE FUS 8 6 d FU4 5 5 O L5 205 YEL 153 2 BLK fo 9 2 T 6 Of rur 162 BLK
126. rd using procedure below 12 PIN PLUG PL 1 ON EASY SELECT BOARD 1 Completely disconnect wire harness from Easy Select Board 2 Jumper the screw terminals one at a time R G R Y Y2 R Y1 R W1 R W2 and check for appropriate voltages on the Easy Select Board pins If proper signals are not present replace Easy Select Board If proper signals are present at the pins and not at 16 pin connector to the motor the wiring harness is defective TROUBLESHOOTING EXAMPLE Motor is not running on a call for heat pump heating after jumpering the Easy Select Board screw terminals as described in Thermostat section above With all thermostat wires removed from Easy Select Board place a jumper wire between R and Y Y2 low voltage screw terminals on the Easy Select Board 1 Check Table 8 for pin number on 16 pin connector associated with the Y Y2 signal The correct pin is 14 The far right column of Table 8 shows that 12vdc should be present between pin 14 and pin 1 common on the 16 pin connector 2 Set meter to read DC voltage Place meter leads between pins 1 common and 14 and check for 12 If signal is present the problem is in the module or motor If signal is not present the problem is either in wiring harness or Easy Select Board These steps can be repeated for other modes of operation To check Easy Select Board 1 Leave jumper wire in place between R and Y Y2 2 Check Table 8 under Volt Meter on Easy Select B
127. ric heater Select sizes that are actually installed Continuous fan set too high for 2 speed applications Set to MED or LO Motor Will Not Stop Allow time for off delay to time out In units built before serial number 0101A any W call will have a 2 minute off delay independent of delay selection This is programmed into the motor and cannot be overridden In units built after 0101A the off delay on any W call is 1 minute and cannot be overridden Some power stealing thermostats could bleed enough voltage to cause motor to run slowly when there is no heating or cooling call Disconnect thermostat wires and wait 2 minutes to see if motor stops If it stops replace thermostat or install resistor per thermostat installation instructions Motor Will Not Start See following section Troubleshooting motor ECM2 Motor and Controls C Troubleshooting motor ECM2 Motor and Controls CAUTION ELECTRICAL OPERATION HAZARD Failure to follow this caution may result in equipment damage or improper operation High voltage is always present at motor Disconnect power to unit before removing or replacing connectors or servicing motor Wait at least 5 minutes after disconnecting power before opening motor The ECM ICM motor used with this product contains two parts the control module and the motor winding section Do not assume the motor or module is defective if it will not start Go through the steps described below before replacing control m
128. roubleshooting steps described below before replacing motor control module or entire motor Motor control module is available as a replacement part VERIFY MOTOR WINDING SECTION WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or possible equipment damage After disconnecting power from the ECM motor wait at least 5 minutes before removing the control section Internal capacitors require time to discharge Minor injury from electrical shock may result from early contact with live metal parts Before proceeding to replace a motor control module 1 Check motor winding section to be sure it is functional 2 Remove motor control module section and unplug winding plug Motor shaft should turn freely resistance between any two motor leads should be similar and resistance between any motor lead and unpainted motor end should exceed 100 000 ohms 3 Failing any of these tests entire ECM motor must be replaced 4 Passing all of the tests motor control module alone can be replaced MOTOR TURNS SLOWLY 1 Low static pressure loading of blower while access panel is removed will cause blower to run slowly Particularly at low airflow requests This is normal do not assume a fault exists 2 Recheck airflow and system static pressure using User Interface service screens with access panel in place NOTE Blower motor faults will not cause a lockout of blower operation Fan coil control will attempt to run
129. s a call for dehumidfication J2 This jumper activates heat staging The jumper connects the W1 and W2 terminals together If either is energized W2 airflow is delivered With the jumper pulled there are separate airflows for W1 and W2 H Airflow Delivery These units deliver airflow depending on the system size selections and operating mode The thermostat energizes a combination of terminals on the Easy Select Board which tells the motor what CFM to deliver The following are typical operating modes and the terminals that should be energized on the Easy Select Board NOTE The DH terminal on the Easy Select Board is for dehumidification It is de energized on a call for dehumidification Variable Speed Motor Logic Sequence The ECM motors in these fan coils are programmed to deliver a variety of airflows The motor goes through COOLING The nominal cooling airflow for these fan coils is 350 CFM per ton Selecting the HI adjust tap increases the airflow to 400 CFM per ton The LO tap decreases airflow to 315 CFM per ton The low adjustment is only active during normal cooling mode Removing the signal from the DH terminal reduces the airflow to 80 of cooling airflow Removing the signal for Superdehumidify reduces the airflow to 50 of cooling HEATING The base heat pump only heating airflow is determined by the SYSTEM TYPE selection on the Easy Select Board If HP EFFICIENCY is selected the airflow is the same as Cooling IF HP COM
130. s first digit of code The number of long flashes indicates second digit of code A short flash is 0 25 seconds on A long flash is 1 second on The time between flashes is 0 25 seconds The time between last short flash and first long flash is 1 second Gy UN GU 29 The LED will be off for 2 5 seconds before repeating code B Fan Coil Control Start Up and System Communications Troubleshooting On power up green COMM LED will be turned off until successful system communications are established this should happen within 10 seconds Once communications with User Interface are successful COMM LED will be lit and held on At the same time amber STATUS LED will be lit and held continuously on until a request for operating mode is received The STATUS LED will be on any time fan coil is in idle mode If at any time communications are not successful for a period exceeding 2 minutes fan coil control will only allow emergency heating or cooling operation using a common thermostat a non communicating outdoor unit and the R C Y O W outdoor unit terminal strip connections and will display Status Code 16 System Communication Fault on amber STATUS LED No further fan coil troubleshooting information will be available at User Interface until communications are re established If COMM LED does not light within proper time period and status code is not displayed 1 Check system transformer high and low voltage to be sure the system is powered
131. s only not in electric heating modes FKAC D Series G reduces airflow in all modes NONE with original motor If upgraded to motor ECM2 motor it may have programming NONE with original motor Replacement motor or module may have programming IF an original motor or module has been replaced it may have Super Comfort Heat and SuperDehumidify capability PROCEDURE 2 PCB LAYOUT AND DESCRIPTION FK4 FV4 40FK NOTE Layout of actual PCB is depicted in Fig 11 and 25 The Easy Select Board is the interface between the ECM motor and other system components The board offers choices of electric heater size outdoor unit size and type comfort or efficiency settings on and off delay profiles and continuous fan speed The installer should select the correct size of components that are being installed in each installation If no selections are made the factory default settings are for the largest heater largest outdoor unit AC system type nominal airflow adjust and 0 90 time delay NOTE Outdoor unit model should have an ARI rating with the variable speed fan coil Some outdoor unit models will not work properly with this fan coil Power for system is supplied from a 230 vac 60 Hz line Class 2 voltage 24 vac nom used for thermostat connections is derived from transformer located in close proximity to PCB The 24 vac secondary circuit includes 5 amp automotive type fuse in SEC2 circuit Connec
132. s requested airflow as defined by signals received from Easy Select Board and its internal programming The major difference is that the FK4B motor reacts to changes in system static pressures to maintain constant airflow Unlike conventional fan coils where static pressure affects airflow the FK4B is a constant airflow unit The blower delivers requested airflow up to about 0 7 in of static pressure The motor is pre programmed and contains airflows for all modes of operation Blower characteristics airflow torque and speed vs static pressure are known from laboratory testing If any 3 characteristics are known the fourth is defined Requested airflow is known because of Easy Select board configuration and thermostat signals Torque is known because it is directly related to armature current which is measured by motor control Speed is measured from its generated back EMF This information is entered into an expression which calculates torque from speed and airflow numbers If calculation does not match stored blower characteristics torque is adjusted every 0 8 seconds until agreement is reached The unit does not directly measure static pressure but does react to a change in static to maintain constant airflow PROCEDURE 1 INTEGRATED CONTROLS AND MOTOR FK4B The motor is similar to the used in FK4A series units but cannot be used as a replacement without some modification to FK4A unit The electronics of motor are built into rear o
133. s when the unit has power applied to it the system most likely has 1 of the following problems a If the transformer is shorting out check the wiring of the transformer a The maximum load on the transformer is 40 VA If the load on the transformer is excessive the low voltage 5 amp fuse will blow to protect the transformer If the load exceeds the VA rating of the transformer a larger VA rated transformer needs to be installed Check the sequencers for excessive current draw b Check the wiring of the heaters If the heater is miswired the fuse may blow Check the diodes shown in Fig 40 for signs of overheating If the heater is miswired correct the miswiring 4 Check T2 and connections on the primary side of the transformer If they are not connected properly the low voltage terminal board cannot supply the 24 v signal to energize the fan relay If the transformer is receiving the correct primary voltage but is not outputting the correct secondary voltage the transformer needs to be replaced the electric heat stages will not turn on but the fan will turn on 1 Check the wiring of the sequencer Pay particular attention to the high and low voltage wiring of the sequencers 2 Check the plug wiring to make sure that it is wired correctly 3 Check the voltage to the sequencer sequencer number receives a 24 vac signal If it is receiving the correct voltage check to see if the sequencer is closing If the
134. sembly See Fig 43 Horizontal Applications only Place horizontal condensate pan into position on coil pan assembly NOTE Installation of horizontal condensate pan is not necessary for upflow or downflow applications 15 16 17 18 19 20 21 22 Slide complete assembly into unit Reinstall fitting panel and reconnect clip securing fitting panel to condensate drain pan Horizontal Applications Only Reinstall horizontal pan clip Secure with 1 screw See Fig 43 Reinstall coil access panel Reconnect liquid and vapor refrigerant tubes and condensate drain tube Install new liquid line filter drier Evacuate tube set and indoor coil to 500 microns back seat open liquid and vapor service valves Turn on electrical supplies to indoor and outdoor units Check system refrigerant charge and operation See Split System Residential Air Conditioners and Heat Pumps Service Manual for further information PROCEDURE 2 SLOPE COIL UNITS If it is determined that system does not have leaks and refrigerant is not contaminated proceed as follows 1 Recover system refrigerant a Attach manifold gage set to service valves b Front seat close liquid tube service valve c Start unit in cooling mode 4 Run unit until low pressure switch opens or vapor pressure reaches 5 psig 35kPa Do not allow compressor to pump into a vacuum e Turn off electrical supply to outdoor unit f Front seat vapor service valve g
135. sequencer is not closing but is receiving the correct voltage replace the sequencer If the sequencer is closing check the high voltage wiring as discussed in 1 and 2 C If the electric heat and the fan will not turn on IF THERE IS NO HIGH VOLTAGE TO THE PCB 1 Check the plug connection This brings power to the PCB transformer and the fan Make sure the plug is connected properly 2 Check sequencer number 1 and the plug wiring The yellow wire should be connected to pin number 9 of the plug and the limit switch The black wire should be connected to pin number 7 of the plug and to sequencer number 1 3 Check incoming high voltage power leads If these are not receiving power the system cannot function IF THE PCB HAS HIGH VOLTAGE APPLIED TO IT 1 Check the low voltage transformer leads R and C Make sure they are wired to the correct location The unit will not function without proper connections 2 Check the output voltage of the secondary side R and C of the transformer If the circuit board is an HK61GA003 make sure the ground strap is in place from C to the bracket This strap must be in place to complete the 24 v circuit If the transformer output is zero vac refer to If the PCB has high voltage applied to it in column 1 numbers 3 and 4 D If the traces are burnt off the back of the PCB Usually whenever there is a trace blown on the PCB it means either there has been a high voltage short or high voltage has been applied
136. sequencer relay 1 is being checked The procedure is the same for all other sequencers relays If 24 volts DC is not observed check the following s room thermostat calling for electric heat This can be confirmed by checking for 24 volts AC between low voltage terminal strip terminals W2T and s LED flashing appropriate code for number of sequencers relays energized In this example 2 flashes should be visible indicating 1 sequencer relay is energized Indicator tells how many sequencers relays are energized but does not tell which ones are s 9 pin connector for heater package tightly secured to control board F Checking Sequencer Operation To check for operation of power circuit of sequencer relay place voltmeter leads across sequencer relay terminal 4 of sequencer relay 1 and terminal 4 of limit switch 3 The reading should be 208 230v and heater should be energized If 208 230v is not observed at terminals specified check the following Are fuses FU3 and FUA good s limit switch LS3 open If so check fan coil air filter or air distribution system for blocking or restriction that might reduce airflow and cause limit switch to open Operation of heaters can be confirmed further by using a clamp on ammeter in circuit shown to verify current is flowing through heaters Amperage readings will depend on size of heater The procedure for checking other sequencers relays in system is identical to that just described G E
137. sformer high voltage supplied from electric heater package or high voltage leads through 12 pin heater connector plug recp2 The ECM2 5 power connections are made at the transformer primary terminals The transformer secondary connections are made at SEC1 and SEC2 connectors PROCEDURE 2 TROUBLESHOOTING FE4 NOTE Always check high and low voltage supply to the fan coil components Check the integrity of the plug receptacle connections and fan coil wiring harness prior to assuming a component failure A LED Description LEDs built into fan coil control provide installer or service person information concerning operation and or fault condition of the fan coil control and ECM motor This information is also available at system User Interface in text with basic troubleshooting instructions Careful use of information displayed will reduce the need for extensive manual troubleshooting The amber LED located at bottom center of control adjacent to motor harness plug is Motor Status LED and it is labeled MOTOR A second amber LED located in upper right center of control adjacent to System Communications connector A B C D is the System Status LED and it is labeled STATUS The green LED labeled COMM is also located adjacent to System Communications connector below STATUS LED and is used as an indicator of system communications status Status Codes will be displayed on the STATUS LED using the following protocol 1 The number of short flashes indicate
138. stat closes R to W and thermostat should be set up to energize G with W This is due to the Super Comfort Heat programming in the motor Energizing W without G will result in 2596 lower airflow delivery The selected delay profile is not active in this mode K Super Comfort Heat Mode This is a special heating mode only available on FK4 FV4 and 40FK fan coils combined with a Thermidistat Control or Comfort Zone II B When this option is selected the indoor control will monitor the outdoor temperature The control will drop the G signal to the fan coil when the outdoor temperature is between 10 and 40 F This triggers the motor to slow to approximately 213 CFM per ton The heaters will stage as needed during this mode and the motor will adjust airflow as required Below 10 F theW1 control output will automatically energize on a call for heat The motor ECM2 power connections are made at the transformer primary terminals The transformer secondary connections are made at SECI and SEC2 connectors PROCEDURE 4 EASY SELECT CONFIGURATION TAPS The Easy Select taps are used by installer to configure system The motor ECM2 uses selected taps to modify its operation to a pre programmed table of airflows Airflows are based on system size and mode of operation and those airflows are modified in response to other inputs such as the need for de humidification See Fig 11 The FV4 and 40FK Fan Coils must be configured to operate properly with sys
139. t there is no effect on PCB No heat is energized C Accessories Terminals AUX and AUX are energized with 24 vdc when fan is energized The accessory kit 101 is used to connect an EAC humidifier NOTE Loads cannot be connected directly to AUX and AUX Use the specified kit only 38 D Blower 1 Blower On Delay To optimize comfort there is a 30 sec blower on delay in heat pump heating mode only 2 Blower Off Delay Smart Heat control uses a 60 sec off blower delay as opposed to the standard 90 sec delay PROCEDURE 3 SMART HEAT OPERATION A Cooling The Smart Heat option controls cooling mode in same manner as conventional heat pumps are controlled The fan has a 90 sec delay off on cycle down B Heat Pump Heating The Smart Heat option does not control heating in the conventional method The PCB energizes compressor 30 sec before indoor fan is energized This allows indoor coil to heat up eliminating cold blow on start up The electric heat is staged on to allow continuous operation of heat pump and electric resistance heat below balance point below point where heat pump cannot maintain dwelling temperature without supplemental heat independent of outdoor thermostats Although PCB has provisions for an outdoor thermostat it is not needed for staging On cycle down indoor fan remains on 60 sec to recover heat stored in indoor coil C Defrost The Smart Heat PCB stages the correct amount of s
140. tablished communications with outdoor unit or select proper size from valid size list provided at User Interface 4 Check motor and motor control module following the instructions in Section C ECM Motor Troubleshooting STATUS CODE 26 INVALID HEATER SIZE On initial power up fan coil control will write into memory electric heater size as read from heater if heater is provided with Identifier Resistor IDR Heater size must be valid for combination of indoor and outdoor components installed Fan coil control will read IDR value connected to pins 5 and 8 of heater harness connector If no resistor is found system User Interface will prompt installer to verify that no heater is installed Verifying that this is correct will establish that fan coil is operating without an electric heater accessory Upon choosing negative option installer will be prompted to select heater size installed from a list of valid heater sizes for fan coil and outdoor unit size installed If heater ID resistor value read is invalid Status Code 26 will be displayed on STATUS LED If heater installed is equipped with a resistor connected to pins 5 and 8 of heater harness connector and status code 26 is displayed on STATUS LED 1 Check wiring harness connections to be sure connections are secure 23 THIS COMPARTMENT MUST BE CLOSED EXCEPT FOR SERVICING CAUTION ATTENTION BLOWER MOTOR NOT SUITABLE FOR USE NE CONVIENT PAS AUX ROTATION ON SYSTEMS EXCEEDING INSTALL
141. tem components with which it is installed To successfully configure a basic system see information printed on circuit board located next to select pins move the 6 select wires to pins which match components used along with homeowner preferences A Auxiliary Heat Range The installer must select the auxiliary heat airflow approved for application with kw size heater installed Each select pin is marked with a range of heaters for which airflow also marked is approved For increased comfort select the narrowest kw range matching the heater size for example 0 10 for a 10 kw heater This airflow must be greater than the minimum CFM for electric heater application with the size system installed for safe and continuous operation Note that airflow marked is the airflow which will be supplied in emergency heat mode and heating mode on air conditioners when electric heat is primary heating source To ensure safe heater operation in heat pump heating mode when electric heaters are energized the motor ECM2 will run the higher of heat pump airflow and electric heater airflow The factory default selection is largest heater range approved See Fig 11 B AC HP Size The factory default setting for air conditioner or heat pump size is largest unit meant for application with model of fan coil purchased The installer needs to select air conditioner or heat pump size to ensure that airflow delivered falls within proper range for size of unit installed in all
142. teristics are known the third is defined Requested airflow is known from Easy Select board configuration and thermostat signals Torque is known because it is directly related to stator current which is measured by motor control Speed is measured by counting back EMF pulses from stator windings This information is entered into an expression which calculates torque from speed and airflow numbers If calculation does not match stored blower characteristics torque is adjusted until agreement is reached This calculation and adjustment is performed every 0 8 sec while motor is in operation There is no direct measure of static pressure but unit does react to a change in static to maintain constant airflow A change in pressure will result in a change in stator speed and torque The motor will begin to adjust on the next sampling calculate new desired speed and torque and adjust as necessary PROCEDURE 1 CONTROLS AND MOTOR ECM 2 An 2 is fed high voltage AC power through the 5 pin connector See Fig 10 The AC power is then internally rectified to DC by a diode module After rectification DC signal is electronically communicated and fed in sequential order to 3 stator windings The frequency of these commutation pulses determines motor speed The rotor is permanently magnetized An motor ECMG is powered with high voltage at all times The motor will not run with high voltage alone Low voltage must be a
143. the bellyband placement around the center of the motor as shown in Fig 41 Do not cover motor vent holes or the motor will overheat Table 15 shows the position of the motor from center Table 15 Replacement Motor Position FA4 FB4 FC4 FX4 030 Out 73 8 FA4 FB4 FC4 FX4 036 FA4 FB4 FC4 FX4 060 In 71 2 FA4 FB4 FC4 FX4 018 024 042 048 ELECTRIC HEATER FUNCTION AND TROUBLESHOOTING This section describes KFA KFB KFC and KFD series electric heaters in exclusion of Smart Heat by examining the functional operation of these heaters PROCEDURE 1 DESCRIPTION OF ELECTRIC HEATER COMPONENTS A Limit Switch The limit switch is a temperature sensitive control whose function is to prevent system from overheating in abnormal conditions The temperature settings often vary from heater to heater due to variations in airflow patterns and element radiant heat conditions The devices are sized to remain on line under heat pump conditions 115 F air off coil and minimum CFM but trip to prevent outlet air conditions above 200 F or excessive component or duct temperatures The device itself consists of a bimetallic disc which when overheated snaps through to open a normally closed high voltage high current switch When system temperatures cool sufficiently the switch will automatically reset to its closed position Normal failure mode for this switch is open If a limit switch has been determined to be defective NEVER BYPASS
144. they are further apart speed is increased with faces closer together Check pulley setscrews and bolts D Cleaning or Replacing Refrigerant Flow Control Device Refer to Fig 24 and instructions given in FD3A Service and Troubleshooting section above UTILITY MOTOR O GROUND LEAD A91151 Fig 25 Wiring Schematic MUST BE PARALLEL FOR PROPER ALIGNMENT PULLEY ALIGNMENT BELT ADJUSTMENT A91150 Fig 26 Checking Pulley Alignment and Tightness PROCEDURE 2 MAINTENANCE A WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect electrical power to all circuits before servicing unit Failure to do so may result in personal injury from electrical shock or moving parts WARNING CUT HAZARD Failure to follow this warning could result in personal injury As with any mechanical equipment personal injury can result from sharp metal edges Be careful when removing parts A Return Air Filter To clean or replace air filter remove screws and filter access door Slide out filter For washable type filters clean with hot soapy water Rinse clean and let dry New filters are available from a local distributor Place filter in slot with filter arrow facing direction of airflow Replace filter access doors with screws previously removed A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment
145. tion to heater panel is made through 12 pin connector PL 1 Connections to thermostat are made at screw terminals Twenty one pin terminals comprise field select taps for motor Fuse Data 5 amp automotive type ATC ATO tan 32 200 percent current opening time of 5 sec maximum A Electrical Connections Twenty one 0 110 in pin terminals are used to provide programming selections for operating modes of motor ECM2 The 6 selection modes are listed below For additional information refer to Easy Select Configuration Taps section AUX Heat Range Violet Wire AC HP Size Blue Wire Type Orange Wire AC HP CFM Adjust Black Wire AC HP Time Delay Grey Wire Continuous Fan Yellow Wire PROCEDURE 3 SEQUENCE OF OPERATION FK4 FV4 40FK A Continuous Fan Mode The thermostat closes circuit R to G The unit delivers the airflow selected for fan only operation B Cooling Mode Single Speed or 2 Speed High Thermostat closes circuits R to G R to Y Y2 and R to O heat pump only A circuit R to Y1 is required for 2 speed high operation Airflow delivered the airflow selected by AC HP SIZE selection and CFM ADJUST selection C Cooling Mode Two Speed Low Thermostat closes to and to and to heat pump only Unit delivers 2 speed low airflow for AC HP SIZE CFM ADJUST selected D Cooling Dehumidify Mode Thermidistat or Comfort Zone II B and Single Speed Outdoor Unit Installed jumper must be pul
146. to provide fan coil operation and troubleshooting information When motor is commanded to operate the MOTOR LED will be turned on and will flash each time instructions are sent to the motor When the motor is commanded to stop the MOTOR LED will be turned off The MOTOR LED will not flash to indicate communications when it is turned off Fan coil control is constantly communicating with the motor even when the motor and MOTOR LED are off If motor does not acknowledge receipt of communications the control will display Status Code 44 on STATUS LED and continue to try to communicate with the motor If motor acknowledges communication status code will be cleared If MOTOR LED is lit and flashing and motor does not run 1 Check the STATUS LED If STATUS LED is indicating a Status 44 code check the motor wiring harness for proper connection to control and motor receptacles 2 Check motor wiring harness to be sure all wiring complies with wiring diagram description makes a complete circuit from connector to connector and is not shorted 3 Check 12 Vdc low voltage supply to motor at pins 1 4 and 2 of motor header connection to fan coil control See wiring diagram Fig 17 If all checks are normal fan coil control is good and control module on motor may need replacement Check motor and Motor Control Module following the instructions in Section C ECM Motor Troubleshooting Shorted or mis wiring of the low voltage motor harness wirin
147. upplemental heat during defrost If too much heat is added system stays in defrost for completion of defrost cycle even though thermostat is satisfied On next cycle 1 less element is energized during next defrost period NOTE If the signal from thermostat is interrupted ie thermostat is satisfied while unit is in defrost mode the defrost cycle will be completed before unit shuts down D Troubleshooting Printed Circuit Board Diagnostic LED The PCB of Smart Heat option heater package contains a microprocessor which controls fan operation fan speed outdoor unit and heater elements For troubleshooting a service LED indicates condition of PCB See Table 12 for LED flash codes Table 12 LED Codes for Smart Heat PCB Flash Condition Input Signals System Operation No Light Flash No Power or D Board Failure Steady Light E o o e Board Failure Steady Flash Stand By Condition Y only Heat Pump Only Operating 2 Flashes Heat Pump Plus 1 Sequencer 3 Flashes Heat Pump Plus 2 Sequencers 4 Flashes Heat Pump Plus 3 Sequencers 5 Flashes Cool Mode 6 Flashes Y W2D and or W2T Defrost Mode 7 Flashes Emergency Heat Mode PROCEDURE 4 ELECTRICAL OPERATING SEQUENCES AND TROUBLESHOOTING NOTE Refer to Table 13 for proper input and output voltages See Fig 28 for Smart Heat Proper Wiring Diagram A Ready To Start In ready to start standby mode LED on board indicates a steady flash In this mode 24 v power should be ava
148. vided below Codes are listed in order of their priority highest to lowest Though multiple faults can exist at any time only the highest priority code will be displayed on STATUS LED Clearing the indicated fault when multiple faults exist will cause the next highest priority Status Code to be flashed All existing faults as well as a fault history can be viewed at User Interface STATUS CODE 45 CONTROL BOARD TEST FAULT Fan coil control has failed internal start up tests and must be replaced No other service procedure will correct STATUS CODE 37 HEATER OUTPUT SENSED WHEN NOT ENERGIZED Fan coil control is provided with circuitry to detect presence of a 24 vac signal on Electric Heater stage 1 and stage 2 outputs If fan coil control detects a 24 vac signal on either heater stage output and it is not supplying signal Status Code 37 will be displayed on STATUS LED Fan coil control will turn off output and command blower motor to supply an airflow determined to be safe for current operation mode with electric heaters energized To find the fault 1 Stop all system operations at User Interface and check heater stage 24 vac outputs 2 Disconnect electric heater at plug receptacle 2 and check heater wiring for faults See Status Code 36 for more information STATUS CODE 44 MOTOR COMMUNICATION FAULT The MOTOR LED is connected to the blower motor communication line and works with the fan coil control microprocessor and STATUS LED
149. was introduced as part of the Comfort Heat Pump system and is identical to the FK4C except it is factory supplied with a Thermidistat Control Both the 40FKA and FK4 R 22 units with a factory supplied R 22 TXV Other than the pressure differences in the Puron system all three units are constant airflow machines and operate the same way The FV4B and FK4D include the added benefits of low sweat low leak cabinet OPTIONAL SAFETY GROUND DRAIN HOLE OX AZ 599 POWER CONNECTOR 1519 11213141 516 7 8 YN DRAIN HOLE CONTROL CONNECTOR OPTIONAL SAFETY GROUND gt CONTROL POWER C C 000 0000 4 00 00004 7 m DRAIN HOLE 98201 Fig 10 FV4A and 40FKA motor ECM2 3 Motor Constant Air Flow Unlike fan coils using induction motors where static pressure affects airflow these fan coils are constant airflow units The blower delivers requested airflow regardless of static pressure Consult fan coil Product Data for static pressure limits The motor ECM2 is pre programmed contains airflow tables for all modes of operation Blower characteristics requested airflow torque and speed are known from laboratory testing If any 2 charac
150. y to close its normally open contacts turning fan on The second occurs when there is a call for electric heat A 24 vac signal is sent to heater sequencer relay causing it to close directing 230v through the normally closed contact of fan relay turning fan on The fan remains on until sequencer relay opens Refer to FF1A FF1B FFIC typical wiring diagram See Fig 21 If motor does run test motor for an open winding or a winding shorted to motor case If any 1 of the 2 is present replace motor PROCEDURE 2 ELECTRIC HEATER SERVICE Service can be completed with heater in place Shut off power before servicing A Limit Switch Refer to Electric Heater Function and Troubleshooting section of this manual 28 n 0 50 27 0 l pm 8 P uM fol 2 Cle Ubby 50 Tee 5 m iH 2 FF1D CONTROL BOX e 2 69 5 eL Ule E 2 1

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