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FEM4, FCM4, FSA4, FEA4, FSM4, FSU4, FXM4

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1. 4 4 4 v 4 4 ped AUX HEAT AC HP KW CFM SIZE SYSTEM AC HP CFM ON OFF TYPE ADJUST DELAY Su CONTINUOUS FAN A96431 Table 2 FVM4X Connections and Connectors Type Connection Type Connector Pin No Description Pin 1 Common to screw terminal G Pin 2 Common to screw terminal Y Y2 through diode D3 Pin 3 Common through Y1 through diode D2 Pin 4 Common to W2 screw terminal Pin 5 Common to W2 screw terminal Pin 6 Common to W1 screw terminal eder eonmection dein Pin 7 Common to W1 screw terminal Pin 8 R 24Vac Pin 9 Common to transformer C Pin 10 Common to transformer C Pin 11 Common to transformer C Pin 12 Common to DH screw terminal Table 3 Typical Operating Modes Operating Mode Heat Pump Only Heating Heat Pump Only Heating Super Comfort Heat Mode Heat Pump Heating Auxiliary Heat non staged Cooling Cooling Dehumidification Cooling Superdehumidification F Heat Pump Heating Mode Single Speed or Two Speed High Thermostat closes R to Y Y2 and R to G A circuit R to Y1 is required for two 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 deli
2. 8 Bottom Rear Plate Note This illustration is for reference only 9 Bottom Plate Assy A13135B Figure 12 FMA4 WAMA WAXA sizes 18 amp 24 Expanded View Duct Components Blower amp Electrical Parts DUCT COMPONENTS 18K amp 24K BLOWER amp ELECTRICAL PARTS DUCT COMPONENTS Ch i 4 Blower Discharge Plate 3 Rear Heater Support Plate I 2 Heater Blank N Off Plate 1 Blower Deck ELECTRICAL PARTS 1 Control Mounting Plate 2 24v Transformer 2 Arm And Grommet 6 SSS 3 Time Delay Rela Ue 4 Blower Relay 3 Blower Motor a VER Z cy 4 Ground Lug 3 Terminal Block Capacitor 6 Capacitor Strap Note This illustration is for A Bawer reference only A13136 18 Specifications subject to change without notice 496 08 8001 01 SERVICE AND MAINTENANCE FAN COILS Figure 13 FMA4 WAMA WAXA sizes 18 amp 24 Expanded View Evaporator Parts amp Drain Pan EVAPORATOR PARTS amp DRAIN PANCI8K amp 24K 7 Distributor Ass 6 Header Ass 4 Coil I 8 B Piston Installed 3 Coil Airproof Plate 8 Throttle 2 Coil Support Plate 9 Distributor 10 Capillary 1 Air Filter Support Plate Note This illustration is for reference only 11 Drain Plug 12 Drain Pan hg Coil Roof Plate A13137B Figure 14 FMA4 WAMA WAXA sizes 30 amp 36 Expanded View Case 30K amp
3. 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 and 2 of motor header connection to fan coil control 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 14 Specifications subject to change without notice FAN COILS Shorted or mis wiring of the low voltage motor harness wiring 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 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 Observer wall control will prompt installer to enter correct model size from a list of valid sizes 3
4. s The distributor used on the all aluminum coils is also made of aluminum The TXV connection to the distributor is accomplished with a 3 4 in Chatleff nut See Figure 18 The threads are coated with Loctite Heavy Duty Anti Seize which is a graphite calcium fluoride formulation for applications that is free from copper lead and sulfur This product is typically FAN COILS used in applications with an operating range of 20 F to 2400 F When replacing a TXV it is recommended to reapply with the same thread sealer Extra care should be taken during brazing of copper equalizer on the aluminum coils to prevent the braze material from splattering on the aluminum Also route the copper equalizer so that it does not touch the aluminum components Figure 18 Aluminum Coil Unit TXV s Thermal Valve lt Figure 19 Refrigerant Flow Control Device FEM4P WAPM WAPT WAPL REM4P BRASS 4 HEX BODY TEFLON SEAL PISTON i PISTON RETAINER BRASS HEX NUT A93530 Piston Body Cleaning and Replacement A CAUTION ENVIRONMENTAL HAZARD Failure to follow this caution may result in environmental damage Do not vent refrigerant to atmosphere Recover during system repair or final unit disposal A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution could r
5. 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 Observer wall control in a fully communicating system 1 If outdoor unit size is invalid Status Code 27 will be displayed on STATUS LED 2 If model size data is missing as is the case when a replacement outdoor control is installed Observer wall control 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 Observer wall control has established communications with outdoor unit or select proper size from valid size list provided at Observer wall control 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 Observer wall control will prompt installer to select heater size installed from a
6. The selected delay profile is not active in this mode Specifications subject to change without notice 496 08 8001 01 SERVICE AND MAINTENANCE EASY SELECT CONFIGURATION TAPS The Easy Select taps are used by installer to configure system The ECM 5 0 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 Figure 5 The FVM4 Fan Coils must be configured to operate properly with system 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 six 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 h
7. 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 13 SERVICE AND MAINTENANCE E Fan Coil Troubleshooting Fan coil faults indicated by flashing codes on the amber system STATUS LED can be resolved using troubleshooting information provided 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 Observer wall control 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 ON 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 c
8. 36K CASE 1 Wrapper Assy 2 Top Plate Ass 3 Blower Assy Panel 4 Upper Filter Panel 3 Lower Filter Panel it 7 Wall Mount Brackets 8 Install Support Plate 9 Bottom Rear Plate Note This illustration is for reference only 10 Bottom Plate Assy A13138B Specifications subject to change without notice 496 08 8001 01 19 SERVICE AND MAINTENANCE FAN COILS Figure 15 FMA4 WAMA WAXA sizes 30 amp 36 Expanded View Duct Components Blower amp Electrical Parts DUCT COMPONENT S 30K amp 36K gt BLOWER amp ELECTRICAL PARTS DUCT COMPONENTS 3 Left Plate 6 Blower Discharge Side Brackets 4 Heater Blank OFF Plate 7_ Support Bracket 3 Blower Discharge 2 Right Plate 1 Blower Deck ELECTRICAL PARTS BLOWER MOTOR E 1 Control Mounting Plate 4 24v Transformer 2 Arm And Grommet BB R Ground Lug 2 Time Delay Relay 3 Blower Motor 3 Blower Rela 6 Capacitor 7 Capacitor Strap 8 BLOWER 4 Terminal Block Note This illustration is for reference only A13139 Figure 16 FMA4 WAMA WAXA sizes 30 amp 36 Expanded View Evaporator Parts amp Drain Pan EVAPORATOR PARTS amp DRAIN PANC30K amp 36K gt 7 Distributor Ass 6 Header Ass Piston Installed 3 Coil Airproof Plate 8 Throttle J Distributor 1 Air Filter Support Plate S 10 Copittary y 2 Coil Support
9. 46 BROWNOUT CONDITION If the secondary voltage of the transformer falls below 15Vac for a period exceeding four seconds Status Code 46 will be displayed on STATUS LED If system includes a non communicating outdoor air conditioner or heat pump the Observer wall control will command the fan coil to turn off Y output controlling compressor When secondary voltage rises above 17Vac for more than four 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 within 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 If 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
10. 90 seconds 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 2 W3 When a signal is sent to W3 a 24 Vac signal to sequencer relay No 2 causes it to close with second stage of electric heat turning on The 24 Vac signal applied to sequencer relay No 1 causes fan to operate Timing is such that sequencer relay No 1 will turn on before sequencer relay No 2 When signal to W3 is turned off sequencer relay No 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 3 E When thermostat sends a signal to E a 24 Vac signal is sent to sequencer relay No 3 The 24 Vac signal applied to sequencer relay No 3 turns on third stage of electric heat The 24 Vac signal applied to sequencer relay No 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 496 08 8001 01 Specifications subject to change without notice FAN COILS NOTE Electric heaters are factory wired with all stages tied together If independent staging is desired consult outdoor thermostat installation instructions or corporate t
11. 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 THE LIMIT SWITCH When replacing limit switch ensure that it is replaced with a limit switch of identical opening temperature and closing differential Contact FAST for replacement part Limits switches are typically color coded to identify their range B 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 or 2 pole normally open device which energizes within 30 to 70 seconds after application of control signal and de energizes 60 to 90 seconds 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 c
12. PL1 2 a 12 Vdc should be present If 12Vdc is not present replace circuit board 14 If Fault Code 44 is flashing and the Motor LED is flashing place a DC voltmeter across terminal PL1 3 and PL1 2 15 Across terminal PL1 3 and PL1 2 the DC volt meter should display 5Vdc The voltage should be very stable and should not fluctuate more than 02Vdc If the voltage fluctuates get a different voltmeter before proceeding to the following steps 16 Reconnect Plug 1 to circuit board and connect DC voltmeter across terminals PL1 3 Yellow and PL1 2 Green Does the voltage appear to fluctuate more than in step 15 Typical voltmeters will show a fluctuation of 2Vdc to 1Vdc The amount of fluctuation amp 16 Specifications subject to change without notice 17 FAN COILS is not important You could see even more fluctuation depending on the voltmeter used Figure 9 FCM4 Circuit Board LED Locations DX DX C R A13031 Figure 10 ECM Plug Wiring Diagram Check the blower motor serial output signal The blinking LED on the control board represents the serial output signal You can measure the signal with a DC voltmeter by removing Plug 1 from the circuit board and connecting the DC voltmeter across PL1 4 and PL1 2 The voltage should be near OVdc but it will fluctuate briefly several times per second If you have an analog voltmeter the needle briefly will go high several times
13. an open drain or sump A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution may 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 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 1 Pull unit disconnect when used and remove blower access panel 2 Disconnect motor electrical leads from control box and capacitor Mark location of wires for reassembly 3 Remove the three 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 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 on blower wheel vanes Do not drop or bend wheel as balance will be affected To reassemble unit proceed as follows 1 Place motor with moun
14. at any time communications are not successful for a period exceeding two 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 Observer wall control 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 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 496 08 8001 01 SERVICE AND MAINTENANCE Check system wiring to be sure Observer wall control is powered and connections are made DX to DX DX to DX etc and wiring is not shorted Mis wiring or shorting of the DX DX C R 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 Observer wall control but may cause low voltage fuse to open FAN COILS C ECM Motor Troubleshooting The ECM motor used in this prod
15. at low airflow requests This is normal do not assume a fault exists 496 08 8001 01 N ail a ao O He O W zZ O O a O X H Zz O O Specifications subject to change without notice YOLOW ONINSdO 340438 3LOSNOOSIC SI HAMOd YILAY SILNNIN S MOTTV NINYYM A12231 2 Recheck airflow using Observer wall control 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 the blower motor as long as the Observer wall control 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 five 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
16. field select taps for motor Fuse Data 5 amp automotive type ATC ATO tan at 32Vac 200 percent current opening time of five seconds maximum Electrical Connections Twenty one 0 110 in pin terminals are used to provide programming selections for operating modes of ECM 5 0 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 SEQUENCE OF OPERATION 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 Two Speed High FAN COILS 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 two 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 R to G and R to Y1 and R to O heat pump only Unit delivers two speed low airflow for AC HP SIZE and CFM ADJUST selected D Cooling Dehumidify Mode J1 jumper must be pulled from Easy Select Board Control closes R to G R to Y Y2 and R to O heat pump only and open R to DH Dehumidification is active when 24Vac is removed from DH terminal Unit delivers 20 percent less airflow E Super Dehumi
17. for two speed applications Using this terminal will deliver about 60 percent 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 percent of cooling airflow J1 jumper pulled with no dehumidistat installed The J1 jumper ties the DH terminal to R and is installed at the factory When pulled a dehumidistat supplies a 24 V 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 percent for better dehumidification 10 Specifications subject to change without notice FAN COILS Airflow Too High Wrong Easy Select Board selection Fan coil is factory set for the largest outdoor unit and largest electric heater Select sizes that are actually installed Continuous fan set too high for two speed applications Set to MED or LO Motor Will Not Stop The off delay on any W call is one 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 two minutes to see if motor stops If it stops replace thermostat or install resistor per thermostat installation instructio
18. has one of the following problems a Check all 24 V wiring for an electrical short 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 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 1 Check plug connection between heaters and board This supplies power to transformer and fan Be sure plug is connected properly 2 Check sequencer relay No 1 and plug wiring Yellow wire should be connected to Pin No 9 of plug and to limit switch Black wire should be connected to Pin No 7 of plug and to sequencer relay No 1 3 Check incoming high voltage power leads If these are not receiving power system cannot function SERVICE AND MAINTENANCE IF TRANSFORMER HAS VOLTAGE APPLIED TO IT 1 Che
19. less than 600 psig Do not install a suction line filter drier in liquid line Wrap all filter driers and service valves with wet cloth when brazing Do not use capillary tube indoor coils 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 all filter driers Do not vent R 410A into the atmosphere Observe all warnings cautions notes and bold text Do not use R 22 TXV Copyright 2014 International Comfort Products Lewisburg TN 37091 USA 28 Specifications subject to change without notice 496 08 8001 01
20. of identical opening temperature and closing differential Limit switches are typically color coded to identify their range B EHK and EHC Electric Heat Relay EHK and EHC 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 five seconds for second stage and eight seconds for third stage When the control signal is removed from the relays all relays will open with no time off delay TROUBLESHOOTING EHK and EHC SERIES ELECTRIC HEATERS A 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 Check 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 18Vac and 30Vac 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 shoul
21. ohms Each lead to lead resistance should be the same within 10 percent 4 If any motor fails any of the three tests do not install a new control module The new control can fail if placed on a defective motor The prior fan coil models with multi speed ECM blower motors used a printed circuit board similar to the PSC models The current fan coils do not use the printed circuit board and rely on the motor control programming to provide the off delay timing Another design aspect of the control board was to provide a resistor in the G circuit in case a power stealing thermostat was used This resistor is no part of the wiring harness as shown on wiring diagram The resistor is a 2 watt 1500 ohm resistor If the resistor has failed open a likely cause is due to the power stealing thermostat Connecting C common may resolve the issue Having an open resistor should not affect the operation of the motor Fan Speed Selection The fan speed selection is done at the motor connector Units with or without electric heaters require a minimum CFM Refer to the unit wiring label to ensure that the fan speed selected is not lower than the minimum fan speed indicated 496 08 8001 01 Specifications subject to change without notice FAN COILS To change motor speeds disconnect the BLUE fan lead from motor connector terminal No 2 factory default position and move to desired speed tap 1 2 3 or 5 Speed taps 1 2 and 3 ha
22. 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 Observer wall control 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 the level of comfort and efficiency expected by the consumer and should only be activated when Observer wall control cannot be replaced immediately SEQUENCE OF OPERATION The FCM4 fan coil is designed for installation with Observer communicating wall control This fan coil will not respond to commands provided by a common thermostat except under 15 SERVICE AND MAINTENANCE certain emergency situations described in the Start Up and Troubleshooting sub section The Observer wall control uses temperature humidity and other data supplied from indoor and outdoor system components to control heating or cooling system for optimum comfort ADVANCED TROUBLESHOOTING Troubleshooting th
23. per second If you have a digital voltmeter with a bar graph it will show a large change in magnitude on the bar graph several times per second If you have a plain digital voltmeter it will show a brief fluctuation in voltage and the magnitude may vary depending on the voltmeter used 496 08 8001 01 SERVICE AND MAINTENANCE FMA4P WAMA FMA4X WAXA A WARNING ELECTRICAL OPERATION 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 one disconnect switch Turn off accessory heater power if applicable Lock out and tag switch with a suitable warning label FAN MOTOR FMA4P WAMA The FMA4P and WAMA motor is three speed ECM direct drive High speed lead is black medium speed lead is red low speed lead is blue and common lead is purple Be sure proper blower speed has been selected The motor is turned on through two 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 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 If motor does n
24. signal is electronically communicated and fed in sequential order to three stator windings The frequency of these commutation pulses determines motor speed The rotor is permanently magnetized An ECM 5 0 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 ECM 5 0 Control Power The ECM 5 0 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 6 Specifications subject to change without notice A13028 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 SEC1 connected to metal standoff marked NOTE The PCB must be mounted with two 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 el
25. units The blower delivers requested airflow regardless of static pressure Consult fan coil Specification Sheet for static pressure limits The ECM 5 0 is pre programmed and contains airflow tables for all modes of operation Blower characteristics requested airflow torque and speed are known from laboratory testing If any two characteristics 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 that 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 seconds 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 INTEGRATED CONTROLS AND MOTOR ECM 5 0 An ECM 5 0 is fed high voltage AC power through the 5 pin connector See Figure 4 The AC power is then internally rectified to DC by a diode module After rectification DC
26. 8 SAFETY CONSIDERATIONS Improper installation adjustment alteration service maintenance or use can cause explosion fire electrical shock or other conditions which may cause death 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 instructions packaged with kits or accessories when installing Follow all safety codes Wear safety glasses protective clothing and work gloves Have a fire extinguisher available Read these instructions thoroughly and follow all warnings or cautions included in literature and attached to the unit Consult local building codes and the current editions of the National Electrical Code NEC NFPA 70 In Canada refer to the current editions of the Canadian Electrical Code CSA C22 1 Specifications subject to change without notice Recognize safety information This is the safety alert symbol A When you see this symbol on the unit and in instruction 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 personal injury o
27. G REFRIGERANT FLOW CONTROL DEVICE FMA4P WAMA The FMA4P and WAMA piston can be removed and cleaned if believed to be plugged This unit s piston is unique and replacements are available from FAST The filter drier should be located on the liquid line at the indoor unit to prevent particulate from plugging the piston FMA4X WAXA The FMA4X and WAXA fan coils use an R 410A TXV The TXV s are preset at the factory and do not need adjustment for reliable operation Reference the outdoor unit instructions to properly charge the unit to the correct subcooling For optimal performance adjust the TXV so that 6 F of superheat is measured at the outdoor unit s vapor service valve when the indoor return air is 80 F DB 67 F WB and outdoor ambient is 82 F DB To increase superheat turn the TXV adjustment stem clockwise no more than one rotation at a time After an adjustment is made wait until the superheat temperature has been stable for 15 minutes before making further adjustments SEQUENCE OF OPERATION 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 se
28. 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 Figure 5 496 08 8001 01 Specifications subject to change without notice FAN COILS 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 Figure 5 The selection options are 1 The standard 90 seconds 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 A 30 seconds on 90 seconds 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 seconds on 150 seconds 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 f
29. NOTE Transformer is fused Do not short circuit D Fan Relay Relay coil is 24 V Check for proper control voltage Replace relay if faulty CLEANING OR REPLACING REFRIGERANT FLOW CONTROL DEVICE Refer to Figure 19 and instructions given in Piston Body Cleaning or Replacement section 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 SEQUENCE OF OPERATION 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 complete The heater sequence SEQ is energized which closes contacts of relay 2 Specifications subject to change without notice FAN COILS 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 start
30. Plate Note This illustration is for reference only 11 Drain Plu 12 Drain Pan 13 Coil Roof Plate A13140 20 Specifications subject to change without notice 496 08 8001 01 SERVICE AND MAINTENANCE ELECTRIC HEATER FUNCTION AND TROUBLESHOOTING FEM4 FCM4 FSA4 FEA4 FXM4 FVM4 WAPM WAPT WAPL WAHM WAHT WAHL WAXM WAXT WAXL REM4 This section describes EHK and EHC series electric heaters by examining the functional operation of these heaters 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 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 THE LIMIT SWITCH When replacing limit switch ensure that it is replaced with a limit switch
31. SERVICE AND MAINTENANCE INSTRUCTIONS VERTICAL HORIZONTAL MULTI POSITION FAN COIL UNITS FEM4 FCM4 FSA4 FEA4 FSM4 FSU4 FXM4 FVM4 FMA4 WAH WAP WAM WAX REM4 NOTE Read the entire instruction manual before starting the installation TABLE OF CONTENTS PAGE SAFETY CONSIDERATIONS 00 00 eee eee 1 INTRODUCTION 00 eee 1 FAN COIL DESCRIPTION AND TROUBLESHOOTING 1 FSMA4P FSU4P FSM4X FSU4X FSA4X 1 FEM4P FEM4X FXM4X FEA4X WAHA WAPM WAPT WAPL WAHM WAHT WAHL WAXM WAXT WAXL REM4P REM4X 000005 5 FVM4X catch ena eein adie Rae a E cae Bae wae ee 6 FOM4X coi scecace de oad wiaoetvae dew laa ees 12 FMA4P FMA4X WAMA WAXA 000 2c eee 17 ELECTRIC HEATER FUNCTION AND TROUBLESHOOTING 00 00 eee ee 21 FEM4 FCM4 FSA4 FEA4 FXM4 FVM4 WAPM WAPT WAPL WAHM WHAT WAHL WAXM WAXT WAXL REM4 000s 21 FMA4 WAMA WAXA 0 00 c cece ences 21 CARE AND MAINTENANCE 0002000 000 22 FEM4P FEM4X FCM4X FXM4X FVM4X WAHA WAPM WAPT WAPL WAHM WAHT WAHL WAXM WAXT WAXL REM4X 000 000s 22 FSA4X FEA4X FMA4P FMA4X WAMA WAXA 23 REFRIGERANT FLOW CONTROL DEVICE 24 Thermostatic Expansion Valve TXV 24 Piston Body Cleaning and Replacement 25 COIL amp CONDENSATE PAN REMOVAL and REPLACEMENT 00 cece eee eee eee 26 R 410A QUICK REFERENCE GUIDE 2
32. after a 90 second 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 1 W2 When thermostat sends a signal to W2 a 24 Vac signal is applied across sequencer relay No 1 causing it to close When sequencer relay No 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 No 1 turns off and sequencer opens after a delay of 60 to
33. al Applications Only Remove horizontal condensate drain pan from coil condensate pan assembly See Figure 20 9 Remove the four coil brackets See Figure 20 10 Remove screws at delta plates and remove coil from vertical condensate drain pan See Figure 20 11 Horizontal Applications Only Remove coil top seal attached with four screws and J shaped tube from original coil and install it in same position on new coil See Figure 20 12 Place coil assembly in plastic condensate pan and secure using four screws through delta plate See Figure 20 13 Horizontal and Upflow Applications Only Attach the four coil brackets to coil pan assembly See Figure 20 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 one screw See Figure 20 Reinstall coil access panel 18 Reconnect liquid and vapor refrigerant tubes and condensate drain tube Install new 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 Chec
34. 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 check for 24Vac 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 electric heaters both outputs are energized and de energized 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 c
35. 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 If applicable Secure motor capacitor under strap and tighten strap screw 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 fan coil control 10 Reconnect electrical power to unit and test fan for proper rotation FSA4 FEA4 FMA4 WAMA WAXA 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 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 A CAUTION CUT HAZARD Failure to follow this caution may result in personal injury Sheet metal parts may have sha
36. ck 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 18Vac 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 circuit This can be prevented by making sure PCB is wired correctly before PCB has power applied to it C If Transformer 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 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 FAN COILS 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 Figure 1 Be sure transformer is not shorting out because thermostat wires are miswired 2 Check wiring of relays as shown in Figure 1 Be sure low voltage and high voltag
37. condensate drain tube Install new R 410A liquid line filter drier 17 Evacuate tube set and indoor coil to 500 microns back seat open liquid and vapor service valves 18 Turn on electrical supplies to indoor and outdoor units 19 Check system refrigerant charge and operation See Application Guideline and Service Manual for R 410A for further information o NOA 27 SERVICE AND MAINTENANCE FAN COILS R 410A QUICK REFERENCE GUIDE R 410A refrigerant operates at 50 70 higher pressures than R 22 Be sure that servicing equipment and replacement components are designed to operate with R 410A R 410A refrigerant cylinders are rose colored Recovery cylinder service pressure rating must be 400 psig DOT 4BA400 or DOT BW400 R 410A systems should be charged with liquid refrigerant Use a commercial type metering device in the manifold hose Manifold sets should be 750 psig high side and 200 psig low side with 520 psig low side retard Use hoses with 750 psig service pressure rating Leak detectors should be designed to detect HFC refrigerant R 410A as with other HFC refrigerants is only compatible with POE oils POE oils absorb moisture rapidly Do not expose oil to atmosphere POE oils may cause damage to certain plastics and roofing materials Vacuum pumps will not remove moisture from oil A liquid line filter drier is required on every unit Do not use liquid line filter driers with rated working pressures
38. cur causing the piston to lodge in a partially open or closed position Specifications subject to change without notice 25 SERVICE AND MAINTENANCE LIQUID TUBE STRAINER In all 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 ALUMINUM COIL REPAIR Repairing leaks on aluminum coils is possible using the aluminum brazing method Specific braze and flux material designed for aluminum are necessary for aluminum brazing A kit containing all materials necessary for making an aluminum coil braze repair is available through FAST kit number 1184905 Do not use a wire brush previously used to clean copper when preparing an aluminum braze site Copper particles in contact with an aluminum coil may cause premature failure Service aluminum coils are also available as a coil repair option COIL amp CONDENSATE PAN REMOVAL AND REPLACEMENT Figure 20 A Coil Component Location HORIZONTAL CONDENSATE EXPANSION DEVICE TXV SHOWN HORIZONTAL COIL TOP SEAL DELTA PLATE i CONDENSATE PAN COIL BRACKET 4 PER UNIT SCREWS DELTA PLATE TO PAN 4 PER UNIT L14S006 A Coil Units If it is determined that system does not have leaks and refrigerant is not contaminated proceed as follows 1 Recover
39. d 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 DX DX C R 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 indicates first digit of code 2 The number of long flashes indicates second digit of code 3 A short flash is 0 25 seconds on A long flash is one second on 4 The time between flashes is 0 25 seconds 5 The time between last short flash and first long flash is 1 second 6 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 Observer wall control 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
40. d have failed in open position If output voltage is zero volts replace switch 496 08 8001 01 Specifications subject to change without notice FAN COILS 5 Check heater relay and PCB EHK and EHC heaters only Control voltage input to PCB should be 24Vac Output to relay should be 18 Vdc minimum If input is present but no output replace PCB If output is present replace relay 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 FMA4 WAMA WAXA This section describes EHK2 series electric heaters by examining functional operation of this heater Service can be completed with heater in place Shut off power before servicing DESCRIPTION OF ELECTRIC HEATER COMPONENTS A Limit Switch The limit switch is a temperature sensitive control that s 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
41. dify Mode This mode is only activated when 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 Table 1 Motor and Modules Model Size Motor Type FVM4X2400 Series B ECM 5 0 FVM4X3600 Series B ECM 5 0 FVM4X4800 Series B ECM 5 0 FVM4X6000 Series B ECM 5 0 Current Blower Motor Required Control Module P N Replacement Kit Number 1185246 1185326 1185247 1185327 1185248 1185328 1185249 1185329 Figure 5 Easy Select Board 1185358 P o1 O 08 0 aan IH AV14d 440 NO O 02 0 AZIS dH OV LOATAS ASVA AdAL WALSAS YOLOW YALVSH NV4 SNONNILNOO 13A isnrdv W49 dH OY O W49 MA LY3H XNY 34J dH LHOJWO9 dH OV g od 0 z g HK61EA006 496 08 8001 01 Specifications subject to change without notice SERVICE AND MAINTENANCE FAN COILS Figure 6 Easy Select Board Schematic SYSTEM DIAGRAM HEATER MOTOR MS COOOD000000 SEC1 SEC2 RelsjaoNjoosers
42. e FCM4 Fan Coil Circuit Board The circuit board Fan Coil part number 1184554 Primary test that should be performed Motor Line Voltage Check 1 Turn off power 240V 2 Remove Plug 3 from ECM motor 3 Turn on power 4 Check Plug 3 terminals 4 and 5 to ensure there are 240V 5 Turn off power 6 Reconnect Plug 3 to motor The following troubleshooting techniques will assist in determining the correct component to replace when the Fan Coil Board presents a Fault Code 44 or 41 1 Disconnect power from the unit 240V 2 Disconnect the DX DX C R connector from the board 3 Disconnect Plug 1 from the board See Figure 10 Turn on power 240 volts 5 After reestablishing power you should receive Fault Code 44 and the motor LED should be off 6 Place a jumper across the R and G terminals on the low voltage terminal block 7 Fault Code 44 should still be flashing 8 The Motor LED should be flashing indicating the board is able to transmit a signal to the motor 9 If Motor LED is not flashing check to ensure that 24V is present across R and C on the low voltage terminal block and that there is a good connection with the R and G jumper 10 If 24V is present and the jumper connections are good 11 Replace the board Check Board 12 If Fault Code 44 and the Motor LED are both flashing place a DC voltmeter across terminals PL1 1 Red to PL1 2 Green See Figure 10 13 Across terminal PL1 1 and
43. 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 Check 208 V and 230 V transformer connections They may be miswired Figure 1 Fan Coil Printed Circuit Board contact FAST for part number A03010 WARNING 4 Specifications subject to change without notice A13032 496 08 8001 01 SERVICE AND MAINTENANCE FEM4P FEM4X FEA4X FXM4 WAHA WAPM WAPT WAPL WAHM WAHT WAHL WAXM WAXT WAXL REM4P REM4X MULTI SPEED ECM FAN MOTOR The multi speed ECM 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 module o
44. eat is primary heating source To ensure safe heater operation in heat pump heating mode when electric heaters are energized the ECM 5 0 will run the higher of heat pump airflow and electric heater airflow The factory default selection is largest heater range approved See Figure 5 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 operational modes See Figure 5 Unpack unit and move to final location Remove carton taking care not to damage unit Inspect equipment for damage prior to installation File claim with shipping company if shipment is damaged or incomplete Locate unit rating plate which contains proper installation information Check rating plate to be sure unit matches job specifications C System Type The type of system must be selected 1 AC air conditioner approx 350 CFM ton 2 HP COMFORT provides lower airflow than air conditioner selection approximately 315 CFM ton in heating mode In cooling mode supplies 350 CFM ton 3 HP EFF provides same airflow for heat pump heating and cooling modes approximately 350 CFM ton The factory setting is AC See Figure 5 D AC HP CFM Adjust Select low nominal or high airflow The factory selection is
45. ectric heater package or high voltage leads through 12 pin heater connector plug2 recp2 The ECM 5 0 power connections are made at the transformer primary terminals The transformer secondary connections are made at SEC1 and SEC2 connectors PCB LAYOUT AND DESCRIPTION NOTE Layout of actual PCB is depicted in Figure 5 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 AHRI 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 Connection to heater panel is made through 12 pin connector PL 1 Connections to thermostat are made at 496 08 8001 01 SERVICE AND MAINTENANCE screw terminals Twenty one pin terminals comprise
46. esult 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 496 08 8001 01 Thermal Expansion Valve 0 SS A14212 2 Recover remaining refrigerant from tubing and coil through gage port on vapor tube service valve Disconnect refrigerant liquid tube from piston body See Figure 19 3 Avoid damaging seal ring or machined surfaces on piston bore and retainer 4 Using small wire with a hook on end of it remove piston from body 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 5 Install new or cleaned piston into body 6 Replace seal ring on retainer 7 The threads are coasted with Loctite Heavy Duty Anti Seize it is recommended to reapply with the thread sealer 8 Reconnect refrigerant tube to piston body 9 Pressurize tubing and coil then leak check 10 Evacuate tubing and 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 deformation of the piston body will oc
47. fication It is de energized on a call for dehumidification Il 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 percent of cooling airflow Removing the G signal 9 SERVICE AND MAINTENANCE which initiates Superdehumidification and reduces the airflow to 50 percent 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 COMFORT 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 Super Comfort Heat mode is initiated when the indoor control removes the G signal from the board This slows the motor to 75 percent of heat pump airflow If the CFM adjust is set to LO it will deliver 67 5 percent of heat pump airflow during Super Comfort Heat mode TROUBLESHOOTING A Troubleshooting Easy Se
48. hermostat instructions TROUBLESHOOTING THE PRINTED CIRCUIT BOARD Use wiring schematics shown in Figure 1 as a guide in troubleshooting PCB unless otherwise noted A If Fan Will Not Turn On from Thermostat IF THERE IS NO HIGH VOLTAGE TO TRANSFORMER 1 Check plug receptacle connection This supplies power from heaters to PCB Fan Relay Be sure plug is connected properly 2 Check sequencer relay No 1 and plug wiring Yellow wire should be connected to Pin No 9 of plug and to limit switch Black wire should be connected to Pin No 7 of plug and to sequencer relay No 1 3 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 Check low voltage transformer leads R red and C brown Be sure they are wired to correct locations 2 Check output voltage of transformer secondary side R red and C brown Be sure transformer output is between 18Vac and 30Vac 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 3 Check low voltage fuse shown in Figure 1 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
49. idify Mode EASY SELECT BOARD TERMINAL HUMIDISTAT eT ae JUMPER A95316 FCM4 Model FCM4 fan coil is designed to be installed with the Observer communicating wall control The FCM4 fan coil will provide airflow at a rate commanded by the Observer wall control The nominal airflow ton rate is 350 CFM ton The Observer wall control will modify the commanded airflow under certain operating modes Refer to the Observer wall control 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 ELECTRONICALLY COMPUTED MOTOR ECM 3 0 An ECM 3 0 is fed 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 ECM 3 0 CONTROL POWER The ECM 3 0 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 Plug 1 Pin 2 then through motor control harness to motor A digital signal is sent from Plug 1 Pins 3 and 4 to communicate with
50. imately 90 seconds after G is de energized The time delay can be defeated by cutting jumper JW1 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 208 V or 230 V terminal on transformer Units are factory wired at 230 V 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 the 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 496 08 8001 01 SERVICE AND MAINTENANCE 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 calls for the fan the signal sent to relay is turned off and relay opens causing fan to turn off
51. imum 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 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 A CAUTION CUT HAZARD Failure to follow this caution may result in personal injury Sheet metal parts may have sharp edges or burrs Use care and wear appropriate protective clothing and gloves when handling parts 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 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 22 Specifications subject
52. ing 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 Control Board contact FAST for part number This section of the service manual describes the PCB by examining the functional operation of the PCB components Printed Circuit Board PCB Component Layout of the actual PCB is depicted in Figure 1 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 PCB power and electric heaters Note the pin numbers on plug 5 A time delay relay circuit keeps fan motor running for approx
53. k system refrigerant charge and operation See Application Guideline and Service Manual for R 410A for further information 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 Front seat close liquid tube service valve Start unit in cooling mode Run unit until low pressure switch opens at 50 psig 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 remaining refrigerant NOTE All condenser coils 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 a 0 0 496 08 8001 01 SERVICE AND MAINTENANCE before vapor pressure reaches 5 psig 85kPa If this occurs turn off electrical supply to outdoor unit immediately front seat vapor service valve and recover any remaining refrigerant Figure 21 Slope Coil Component Location COIL MOUNTING CREW SLOPE COIL SKI REFRIGERANT COIL TO CONNECTIONS PAN SCREW BOTH SIDES A98113 2 Turn off electrical supply to indoor unit 3 Disconnect condensate drain tube A CAUTION PERSONAL INJURY HAZARD Failure t
54. lect Board FVM4 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 and thermostat wiring See Figure 5 Be sure transformer is not shorting out because thermostat wires are miswired 2 Check wiring of relays See Figure 5 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
55. 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 2 If symptoms persist 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 496 08 8001 01 SERVICE AND MAINTENANCE NOTE Fan coil control will not operate electric heater until this Status Code is resolved If the heater size is set through the Observer wall control 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 Table 5 FCM4 self identifying resistor values Heater Size Resistor Ohms kW Nominal No heater Open 9 11k 15 18k 20 24k 24 33k 30 39k 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
56. mbly against blower deck flange and slide assembly out of cabinet 4 If applicable 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 5 Loosen setscrew holding blower wheel onto motor shaft 6 Remove the three bolts holding 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 496 08 8001 01 SERVICE AND MAINTENANCE weights clips on blower wheel vanes Also do not drop or bend wheel as balance will be affected To reassemble blower 1 Place blower wheel back into housing Be sure to position correctly for proper location 2 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
57. n Pin No 14 and Pin No 1 common on the 16 pin connector 2 Set meter to read DC voltage Place meter leads between Pins No 1 common and No 14 and check for 12Vdc 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 4 under Volt Meter on Easy Select Board Plug column and row for Pin No 14 on motor plug to see pin number on Easy Select Board that should have voltage The correct pin is No 2 The column on far right will show voltage that should be present between Pin No 2 and Pin No 9 common 3 Place meter leads between Pins No 2 and No 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 two motor leads should be similar 2 The resistance between any motor lead and the unpainted motor end plate should be greater than 100 000 ohms If motor winding fails one of these tests it is defective and must be replaced F Dehumidify Mode NOTE Humidistat mus
58. ns Motor Will Not Start See following section Troubleshooting ECM 5 0 Motor and Controls C Troubleshooting ECM 5 0 Motor and Controls A CAUTION ELECTRICAL OPERATIONS 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 five 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 module 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 five 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 A CAUTION ELECTRICAL OPERATION HAZARD Failure to follow this caution may result in equipment damage or im
59. o follow this caution could result in personal injury Use of torch may cause oil to catch fire resulting in personal injury or death To remove components use tubing cutter only 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 496 08 8001 01 Specifications subject to change without notice FAN COILS Remove coil access and fitting panels Remove 1 screw securing coil to unit casing Remove coil pan assembly from unit Place assembly on a flat surface Remove the two screws securing coil support columns to pan See Figure 21 9 Rotate columns 90 pull away from coil and remove columns from assembly 10 Remove the remaining two screws securing coil to condensate pan 11 Remove coil from condensate pan 12 Remove coil top seal See Figure 21 13 Install new coil into condensate pan using the two original screws and two support columns NOTE Correct coil position in condensate pan is essential to reliable operation 14 Install new coil pan assembly into unit Secure with the two screws previously removed from unit casing 15 Reinstall coil access and fitting panels 16 Reconnect liquid and vapor refrigerant tubes and
60. off HSO TXV The hard shutoff TXV has no bleed port and allows no bleed through after system is shutdown The TXV 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 The bi flow TXV 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 psig 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 24 Specifications subject to change without notice A86006 ope
61. ontrol 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 two 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 connections and will display Status Code 16 on the amber STATUS LED see 496 08 8001 01 Specifications subject to change without notice FAN COILS section E Emergency Heating and Cooling Modes No further fan coil troubleshooting information will be available at the Observer wall control until communications are reestablished Check system wiring to be sure the Observer wall control is powered and connections are made DX to DX DX to DX etc and wiring is not shorted Mis wiring or shorting of the DX DX C R 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 Observer wall control but may cause the low voltage fuse to open STATUS CODE
62. ontrol 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 Observer wall control 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 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
63. ontrols 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 21 SERVICE AND MAINTENANCE 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 CARE AND MAINTENANCE FEM4 FCM4 FXM4 FVM4 WAP WAH WAX REM4 To continue high performance 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 A 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 min
64. ot run test motor for an open winding or a winding shorted to motor case If either is present replace motor FMA4X WAXA The FMA4X and WAXA motor is five speed direct drive The cooling speed tap is selected by connecting the green wire to the desired motor tap number indicated on the motor plug For the electric heat fan speed selection connect the white wire to the desired motor tap number indicated on the motor plug The blower motor in this unit has blower on and blower off delays The blower on delay is 0 30 seconds and will keep the motor running after a heating or cooling call ends If motor does not run test motor for an open winding or a winding shorted to motor case If either is present replace motor ELECTRIC HEATER SERVICE Service can be completed with heater in place Shut off power before servicing A Limit Switch Refer to Electric Heater Kit Function and Troubleshooting section of this manual B Sequencer Refer to Electric Heater Kit 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 496 08 8001 01 Specifications subject to change without notice FAN COILS D Fan Relay Relay coil is 24 V Check for proper control voltage Replace relay if faulty CLEANING OR REPLACIN
65. plicable Lock out and tag switch with a suitable warning label 496 08 8001 01 4 2 2014 SERVICE AND MAINTENANCE FAN COIL DESCRIPTION AND TROUBLESHOOTING PSC FAN MOTOR FSM4 FSU4 FSA4 The PSC motor is two or three speed direct drive High speed lead is black low speed lead is red and common lead is yellow Be sure proper blower speed has been selected The motor is turned on through two 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 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 If motor does not run test motor for an open winding or a winding shorted to motor case If either is present replace motor 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 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
66. proper operation DO NOT remove or apply 5 pin plug on motor with power on Arcing could occur which can damage control module Turn power back on and check the following 3 Check for 24Vac on SEC1 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 496 08 8001 01 SERVICE AND MAINTENANCE Use following procedure to check 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 p
67. r death CAUTION is used to identify unsafe practices which may result in minor personal injury or product and property damage NOTE is used to highlight suggestions which will result in enhanced installation reliability or operation 4 amp CAUTION UNIT OPERATION AND SAFETY HAZARD Failure to follow this caution may result in equipment damage improper operation or personal injury When coils are pressurized with nitrogen open the suction port first to release the nitrogen Mesh screens may dislodge if the liquid line is opened first A WARNING UNIT OPERATION AND SAFERTY HAZARD Failure to follow this warning could result in personal injury or death R 410A systems operate at higher pressures than R 22 systems Do not use R 22 service equipment or components on R 410 equipment Ensure service equipment is rated for R 410A INTRODUCTION These fan coil units are designed for flexibility in a variety of applications that meet 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 5kW 240Vac through 30kW 240Vac 4 WARNING ELECTRICAL OPERATION HAZARD Failure to follow this warning could result in personal injury or death Before installing or servicing unit always turn off all power to unit There may be more than one disconnect switch Turn off accessory heater power if ap
68. r entire motor The control module is available as a replacement part A Itis normal for the motor to rock back and forth on startup Do not replace the motor if this is the only problem identified B If the motor is not running 1 Check for proper high voltage and ground at the L G and N connections at the motor Correct any voltage issue before proceeding to the next step 2 The motor is communicated through 24 Vac signals to the 1 2 3 4 5 and C common terminals Not all taps are programmed if low voltage is applied to an non programmed terminal the motor will not operate which is normal Verify the part number of the motor matches the correct replacement motor part number for the unit model number 3 Initiate a demand from the thermostat and check the voltage between C common and terminal 1 5 If voltage is present and the motor isn t operating then the motor control module is failed C Prior to installing the replacement control module the motor section condition needs to be verified 1 Check to see if the blower wheel spins freely 2 To check for short to ground use an ohmmeter to measure the resistance from any one of the motor connector pins to the aluminum end plate of the motor This resistance should be greater than 100 000 ohms 3 Check the motor phase to phase resistance between each of the leads in the three pin motor connector The lead to lead resistance across any two leads should be less than 20
69. rating 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 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 NOTE 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 5 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 valve The refrigerant flow is effectively stabilized to load demand with negligible change in superheat 496 08 8001 01 SERVICE AND MAINTENANCE ALUMINUM COIL UNIT TXV
70. rocedure 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 2 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 board 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 FAN COILS 1 Check Table 4 for pin number on 16 pin connector associated with the Y Y2 signal The correct pin is No 14 The far right column of Table 4 shows that 12Vdc should be present betwee
71. rp edges or burrs Use care and wear appropriate protective clothing and gloves when handling parts A Air Filter The air filter should be replaced as needed A CAUTION UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage Never operate unit without a filter 496 08 8001 01 Specifications subject to change without notice FAN COILS 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
72. 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 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 close 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 85kPa 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 26 Specifications subject to change without notice FAN COILS 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 Horizont
73. t attached on flat horizontal surface with shaft up 2 Set inlet ring on top of motor mount grommets Center inlet ring flush on all three grommets 3 Slide blower wheel onto motor shaft with setscrew upward and aligned with shaft flat portion Vertically 23 SERVICE AND MAINTENANCE 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 Figure 17 4 Hold blower wheel in place and carefully tighten setscrew 5 Position motor and blower wheel assembly to blower housing as originally oriented FAN COILS 6 Secure motor mount to blower housing using bolts previously removed 7 Attach green wire to blower housing with screw 8 Connect electrical and capacitor leads to original terminals 9 Replace blower access door and tighten all four screws 10 Reinsert disconnect pullout only after blower access door is secured Test blower for proper operation Figure 17 Motor Inlet Ring and Blower Wheel Assembly BLOWER a WHEEL i REFRIGERANT FLOW CONTROL DEVICES Thermostatic Expansion Valves TXV The FSA4X FEA4X FEM4X FXM4X FCM4X FVM4 WAHM WAHT WAHL WAXM WAXT WAXL and REM4X Fan Coils are factory equipped with a hard shut
74. t on AUTO the circuit between R and W is complete 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 17 SERVICE AND MAINTENANCE FAN COILS Figure 11 FMA4 WAMA WAXA sizes 18 amp 24 Expanded View Case 18K amp 24K Case 3 Blower Assy Panel 4 Upper Filter Panel 7 Wall Mount 3 Lower Filter Panel Brackets
75. t open on humidity rise Latent capacities for systems using the FVM4 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 FVM4 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 Carefully consult product airflow data for cooling and dehumidification modes Table 4 FVM4 Motor Control Test Values With 16 pin connector at motor unplugged Terminals Volt Meter on 16 pin Harness Volt Meter on 12 pin Voltage Jumpered Plug Easy Select Board Plug R to W1 Pin 2 Pin 1 Pin 7 Pin 9 24Vac R to W2 Pin 13 Pin 1 Pin 4 Pin 9 24Vac R to Y1 Pin 6 Pin 1 Pin 3 Pin 9 12Vdc R to Y Y2 Pin 14 Pin 1 Pin 2 Pin 9 12Vdc R to G LO Pin 15 Pin 1 Pin 3 Pin 9 OVac R to G MED Pin 6 Pin 1 Pin 3 Pin 9 12Vdc R to G HI Pin 14 Pin 1 Pin 2 Pin 9 12Vdc 496 08 8001 01 Specifications subject to change without notice 11 SERVICE AND MAINTENANCE Figure 7 Humidistat Wiring for De Hum
76. 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 SEC1 connected to metal standoff NOTE The PCB must be mounted with two 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 ECM 3 0 power connections are made at the transformer primary terminals The transformer secondary connections are made at SEC1 and SEC2 connectors 12 Specifications subject to change without notice FAN COILS TROUBLESHOOTING 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 the Observer wall control in text with basic troubleshooting instructions Careful use of information displayed will reduce the nee
77. to change without notice FAN COILS 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 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 may 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 BLOWER MOTOR AND WHEEL Clean blower motor and wheel when cooling coil is cleaned A WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death Disconnect electrical power before removing any access panels Lock out and tag switch with a suitable warning label To clean blower motor or blower wheel 1 Remove blower access panel 2 Remove motor leads from fan coil control Note lead location for ease of reassembly 3 Remove the two outside screws holding blower motor asse
78. uct 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 troubleshooting steps described below before replacing motor control module or entire motor Motor control module is available as a replacement part Figure 8 FCM4 ECM 3 0 Motor POWER CONNECTOR PL14 VERIFY MOTOR WINDING SECTION A WARNING ELECTRICAL SHOCK HAZARD Failure to follow this warning could result in personal injury or death or possible equipment damage After disconnecting power from the ECM motor wait at least five 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
79. unctions See Figure 5 The possible selections are 1 LO provides 50 percent of Y Y2 Cool airflow 2 MED provides 65 percent of Y Y2 Cool airflow 71 percent on 5 ton model 3 Hl provides 100 percent 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 J1 This jumper must be pulled to activate dehumidification mode The jumper connects R to DH With the jumper in the DH terminal is always energized With the jumper pulled the DH terminal is de energized A thermostat capable of a DEHUM feature must be used to supply the 24 V signal when there is no call for dehumidification and turn off the 24 V when there is 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 dehumidi
80. ve a 90 second blower off time delay pre programmed into the motor Speed tap 4 is used for electric heat only with 0 second blower time delay and the WHITE wire should remain on tap 4 Speed tap 5 is used for high static applications but has a O second blower time delay pre programmed into the motor See Airflow Performance tables for actual CFM Also see Figure 3 for motor speed selection location NOTE In low static applications lower motor speed tap should be used to reduce possibility of water being blown off coil Tap 1 Low 90 sec off delay Tap 2 Medium 90 sec off delay Tap 3 High 90 sec off delay Tap 4 Electric heat t 0 sec off delay Tap 5 Max 0 sec off delay t electric heat airflow is same CFM as Tap 3 except 0 sec off delay high static applications see airflow tables for max airflow Figure 3 Motor Speed Selection TWO MOTOR STYLES T OwO Speed Taps may be located on motor or on plug close to motor A11048 SERVICE AND MAINTENANCE FAN COILS Figure 4 FVM4 motor ECM 5 0 Motor A 5 g 3 f g BEFOF FVM4 Constant Air Flow Unlike fan coils using induction motors where static pressure affects airflow these fan coils are constant airflow
81. vers two speed low airflow for AC HP SIZE and CFM ADJUST selected Selected delay profile is active in this mode H Non Staged Auxiliary 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 percent The elected delay profile is not active in this mode 8 Terminals Energized R Y Y2 G DH R Y Y2 DH R Y Y2 G DH W2 R Y Y2 G DH O R Y Y2 G O R Y Y2 O 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 heat staging option where the indoor control can be configured for three 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 Thermostat 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 25 lower airflow delivery

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