XC21 Series - HvacPartsShop.com
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1. Yellow Alert Flash Code 3 Short Cycling Compres sor is running only briefly 1 Thermostat demand signal is intermittent 2 Time delay relay or control board is defective 3 If high pressure switch is present see Flash Code 2 information 4 If low pressure switch is present see Flash Code 1 information Yellow Alert Flash Code 4 Locked Rotor 1 Run capacitor has failed 2 Low line voltage contact utility if voltage at disconnect is low 3 Excessive liquid refrigerant in the compressor 4 Compressor bearings are seized Yellow Alert Flash Code 5 Open Circuit 1 Outdoor unit power disconnect is open 2 Unit circuit breaker or fuse s is open 3 Unit contactor has failed to close 4 High pressure switch is open and requires manual reset 5 Open circuit in compressor supply wiring or connections 6 Unusually long compressor protector reset time due to extreme ambi ent temperature 7 Compressor windings are damaged Yellow Alert Flash Code 6 Open Start Circuit Cur rent only in run circuit 1 Run capacitor has failed 2 Open circuit in compressor start wiring or connections 3 Compressor start winding is damaged Yellow Alert Flash Code 7 Open Run Circuit Current only in start circuit 1 Open circuit in compressor start wiring or connections 2 Compressor start winding is damaged Yellow Alert Flash Code 8 Welded Contactor Com2. LENNOX J UNIT INFORMATION XC21 m Corp 0504 L2 Service Literature Revised 07 2006 XC21 SERIES UNITS The XC21 is a high efficiency residential split system con densing unit which features a two stage scroll compressor and R 410A refrigerant Units are available in 2 3 4 and 5 ton sizes The series is designed for use with an expansion valve only approved for use with R 410A in the indoor unit This manual is divided into sections which discuss the major components refrigerant system charging proce dure maintenance and operation sequence Information contained in this manual is intended for use by qualified service technicians only All specifications are subject to change 4 CAUTION Physical contact with metal edges and corners while applying excessive force or rapid motion can result in personal injury Be aware of and use caution when working nearby these areas during installation or while servicing this equipment A IMPORTANT Operating pressures of this R 410A unit are higher than pressures in R 22 units Always use service equipment rated for R 410A AWARNING Improper installation adjustment alteration service or maintenance can cause property damage person al injury or loss of life Installation and service must be performed by a qualified installer or service agency AWARNING Electric shock hazard Can cause injury or death Before attempting to perform any service or maintenance turn
3. N 1 With both manifold valves closed connect the cylinder of R 410A refrigerant Open the valve on the R 410A cylinder vapor only w 1 Open the high pressure side of the manifold to allow R 410A into the line set and indoor unit Weigh in a trace amount of R 410A A trace amount is a maxi mum of 2 ounces 57 g refrigerant or 3 pounds 31 kPa pressure Close the valve on the R 410A cylinder and the valve on the high pressure side of the manifold gauge set Disconnect R 410A cylinder 4 Connect a cylinder of nitrogen with a pressure regulat ing valve to the center port of the manifold gauge set al Adjust nitrogen pressure to 150 psig 1034 kPa Open the valve on the high side of the manifold gauge set in order to pressurize the line set and the indoor coil O 1 After a few minutes open a refrigerant port to check that an adequate amount of refrigerant has been add ed for detection refrigerant requirements will vary with line lengths Check all joints for leaks Purge ni trogen and R 410A mixture Correct any leaks and re check Page 15 B Evacuating the System Evacuating the system of noncondensables is critical for proper operation of the unit Noncondensables are defined as any gas that will not condense under temperatures and pressures present during operation of an air conditioning system Noncondensables and water vapor combine with refrigerant to produce substances that corrode copper
4. The controller is primarily an a c to d c converter Con verted d c power is used to drive the motor The control ler contains a microprocessor which monitors varying conditions inside the motor such as motor workload The controller uses sensing devices to know what position the rotor is in at any given time By sensing the position of the rotor and then switching the motor windings on and off in sequence the rotor shaft turns the blower Internal Operation The condenser fan motor is a variable speed motor with RPM settings at 700 Y1 and 820 Y2 The variation in speed is accomplished each time the controller switches a stator wind ing figure 11 on and off it is called a pulse The length of time each pulse stays on is called the pulse width By vary ing the pulse width the controller varies motor speed called pulse width modulation This allows for precise control of motor speed and allows the motor to compensate for varying load conditions as sensed by the controller In this case the controller monitors the static workload on the motor and var ies motor rpm in order to maintain constant airflow cfm Motor rpm is continually adjusted internally to maintain constant static pressure against the fan blade The control ler monitors the static work load on the motor and motor amp draw to determine the amount of rom adjustment Blower rom may be adjusted any amount in order to main tain a constant cfm
5. 2 7 8 22 2 7 8 22 2 1 1 8 28 6 Refrigerant 1 R 410A charge furnished 12 lbs O oz 5 4 12 Ibs 5 oz 5 6 13 lbs O oz 5 9 13 lbs O oz 5 9 kg kg kg kg Outdoor Net face area sq ft m2 Outer coil 26 92 2 50 26 92 2 50 26 92 2 50 26 92 2 50 Coil Inner coil 26 07 2 42 26 07 2 42 26 07 2 42 26 07 2 42 Tube diameter in mm 5 16 0 52 5 16 0 52 5 16 0 52 5 16 0 52 No of rows 2 2 2 2 Fins per inch m 22 866 22 866 22 866 22 866 Outdoor Diameter in mm 26 660 26 660 26 660 26 660 Fan No of blades 3 3 3 3 Motor hp W 1 3 249 1 3 249 1 3 249 1 3 249 Cfm L s 1st stage 2800 1320 2800 1320 2800 1320 2800 1320 2nd stage 3400 1605 3400 1605 3400 1605 3400 1605 Rpm ist stage 700 700 700 700 2nd stage 820 820 820 820 Watts 1st stage 70 96 150 150 2nd stage 105 140 220 220 Shipping Data Ibs kg 1 pkg 314 142 331 150 337 153 357 162 ELECTRICAL DATA Line voltage data 60hz 208 230V 1ph 208 230V 1ph 208 230V 1ph 208 230V 1ph 3 Maximum overcurrent protection amps 25 40 50 60 2 Minimum circuit ampacity 15 7 23 7 29 3 34 9 Compressor Rated load amps 10 3 16 7 21 2 25 7 Locked rotor amps 52 82 96 118 Power factor 0 98 0 98 0 98 0 98 Full load amps 2 8 2 8 2 8 2 8 OPTIONAL ACCESSORIES must be ordered extra Compressor Hard Start Kit 10J42 81J69 Compressor
6. ANGLE FOR INSTALLATION lt Remove 4 screws to remove panel for accessing compressor and controls Detail D AO Lo tt FIGURE 3 FIGURE 2 Page 3 ELECTROSTATIC DISCHARGE ESD Precautions and Procedures 44 CAUTION Electrostatic discharge can affect electronic components Take precautions during unit instal lation and service to protect the unit s electronic controls Precautions will help to avoid control exposure to electrostatic discharge by putting the unit the control and the technician at the same electrostatic potential Neutralize electro static charge by touching hand and all tools on an unpainted unit surface before performing any service procedure A Two Stage Scroll Compressor B1 TWO STAGE MODULATED SCROLL slider ring solenoid actuator coil FIGURE 4 The scroll compressor design is simple efficient and re quires few moving parts A cutaway diagram of the scroll compressor is shown in figure 1 The scrolls are located in the top of the compressor can and the motor is located just below The oil level is immediately below the motor The scroll is a simple compression concept centered around the unique spiral shape of the scroll and its inherent properties Figure 5 shows the basic scroll form Two iden tical scrolls are mated t
7. Low Ambient Cut Off 45F08 Compressor Time Off Control 47327 Freezestat 3 8 in tubing 93G35 1 2 in tubing 39H29 5 8 in tubing 50A93 Indoor Blower Relay 40K58 Low Ambient Kit 68M04 Mounting Base 69J07 SignatureStat Home Comfort Controller 81M27 Refrigerant 15 65 15 L 15 65 40 Line Sets 15 65 30 15 65 50 Field Fabricate Time Delay Relay 58M81 NOTE Extremes of operating range are plus 10 and minus 5 of line voltage 1 Refrigerant charge sufficient for 15 ft 4 6 m length of refrigerant lines 2 Refer to National or Canadian Electrical Code manual to determine wire fuse and disconnect size requirements 3 HACR type breaker or fuse Page 2 l APPLICATION Remove the louvered panels as follows All major components indoor blower and coil must be 1 Remove 2 screws allowing the panel to swing open matched according to Lennox recommendations for the slightly compressor to be covered under warranty Refer to the En gineering Handbook for approved system matchups A misapplied system will cause erratic operation and can re sult in early compressor failure 2 Hold the panel firmly throughout this procedure Rotate bottom corner of panel away from hinge corner post until lower 3 tabs clear the slots see figure 3 De tail B 3 Move panel down until lip of upper tab clears the top A CAUTION slot in corner post see figure 3 D
8. Seals not shifting replace compressor b Slider ring not shifting replace compressor B Capacitor C5 The compressor uses a permanent split capacitor see unit wiring diagram The capacitor is located inside the unit con trol box Ratings are on capacitor side C High Pressure Switch S4 44 IMPORTANT Pressure switch settings for R 410A refrigerant will be significantly higher than units with R 22 A manual reset single pole single throw high pressure switch is located in the liquid line The switch shuts off the compressor by de energizing K1 when liquid line pressure rises above the factory setting The switch is normally closed and is permanently adjusted to trip open at 590 10 psi See figure 1 for switch location D Low Pressure Switch S87 All XC21 units are equipped with an auto reset single pole single throw low pressure switch is located in the va por line This switch shuts off the compressor by de ener gizing K1 when vapor line pressure drops below the factory setting The switch is closed during normal operating pres sure conditions and is permanently adjusted to trip open at 40 5 psi The switch automatically resets when vapor line pressure rises above 90 5 psi See figure 1 for switch location E Contactor K1 The compressor is energized by a contactor located in the control box XC21 units are single phase with single pole con tactors See figure 1 for location A DANGER Shock Hazar
9. The amount of adjustment is deter mined by the incremental taps which are used and the amount of motor loading sensed internally The motor constantly adjusts rpm to maintain a specified cfm Page 8 Initial Power Up When line voltage is applied to the motor there will be a large inrush of power lasting less than 1 4 second This in rush charges a bank of DC filter capacitors inside the con troller If the disconnect switch is bounced when the discon nect is closed the disconnect contacts may become welded Try not to bounce the disconnect switch when ap plying power to the unit The DC filter capacitors inside the controller are connected electrically to the speed tap wires The capacitors take approximately 5 minutes to discharge when the disconnect is opened For this reason it is necessary to wait at least 5 minutes after turning off power to the unit before attempting to change speed taps A DANGER Disconnect power from unit and wait at least five minutes to allow At start up the motor may gently rock back and forth for a moment This is normal During this time the electronic controller is determining the exact position of the rotor Once the motor begins turning the controller slowly eases the motor up to speed this is called soft start The motor may take as long as 10 15 seconds to reach full speed Ifthe motor does not reach 200 rpm within 13 seconds the motor shuts down Then the motor will im mediately a
10. and remove the manifold gauge set C Charging AIMPORTANT Mineral oils are not compatible with R 410A If oil must be added it must be a polyol ester oil Weighing in the Charge TXV Systems Outdoor Temp lt 65 F 18 C If the system is void of refrigerant or if the outdoor ambient temperature is cool the refrigerant charge should be weighed into the unit Do this after any leaks have been re paired 1 Recover the refrigerant from the unit 2 Conduct a leak check then evacuate as previously outlined 3 Weigh in the unit nameplate charge If weighing facilities are not available or if you are charging the unit during warm weather follow one of the other proce dures outlined below Subcooling Method Outdoor Temp lt 65 F 18 C When the outdoor ambient temperature is below 65 F 18 C use the subcooling method to charge the unit It may be necessary to restrict the air flow through the out door coil to achieve pressures in the 325 375 psig 2240 2585 kPa range These higher pressures are nec essary for checking the charge Block equal sections of air intake panels and move obstructions sideways until the liq uid pressure is in the 325 375 psig 2240 2585 kPa range See figure 18 Blocking Outdoor Coil Outdoor coil should be blocked one side at a time with cardboard or plastic sheet until proper testing pressures are reached cardboard or plastic sheet FIGURE 18 Four sided un
11. only output a 6 to 18VDC signal which will be insuffi cient voltage to pull the solenoid coil in for second stage Page 7 If compressor solenoid is still not shifting to high capac ity this check will verify that DC power is being fed from the LSOM Il 1 Shut power off to unit main and low voltage 2 Unplug the 2 pin solenoid plug from the fusite connec tion on the compressor and the plug end from the LSOM Il 3 Using an OHM meter check for continuity on the plug harness wire ends red to red black to black Wires should have continuity between same colors and no continuity between opposite color wires If the above checks verify that the solenoid plug is pro viding power to cycle into high capacity operation con tinue to step 3 to determine if problem is with solenoid coil in compressor STEP 3 Confirm internal unloader solenoid has prop er resistance 1 Shut all power off to unit main and low voltage 2 Unplug the molded plug from the compressor solenoid 2 pin fusite 3 Using a volt meter set on the 200 ohm scale Replace the Compressor under these conditions Bad Solenoid a Measure the resistance at the 2 pin fusite The resist ance should be 32 to 60 ohms depending on compressor temperature If no resistance replace compressor b Measure the resistance from each fusite pin to ground There should not be continuity to ground If so lenoid coil is grounded replace compressor Good Solenoid a
12. pressor always runs 1 Compressor contactor failed to open 2 Thermostat demand signal not connected to module Yellow Alert Flash Code 9 Low Voltage Control cir cuit lt 17VAC 1 Control circuit transformer is overloaded 2 Low line voltage contact utility if voltage at disconnect is low Flash code number corresponds to a number of LED flashes followed by a pause and then repeated Reset ALERT flash code by removing 24VAC power from monitor last code will display for 1 minute after monitor is powered on Page 11 I Lennox System Operation Monitor A132 The Lennox system operation monitor LSOM is a 24 volt powered module see diagnostic module A132 on wiring diagram and figure 15 wired directly to the indoor unit The LSOM is located in the control box and is used to trouble shoot problems in the system The module has three LED s for troubleshooting GREEN indicates power status YEL LOW indicates an abnormal condition and RED indicates thermostat demand but compressor not operating See table 3 for troubleshooting codes The diagnostic indicator detects the most common fault conditions in the air conditioning system When an abnor mal condition is detected the module communicates the specific condition through its ALERT and TRIP lights The module is capable of detecting both mechanical and elec trical system problems See figure 15 for the system opera tion monitor Lennox System Opera
13. the electrical power to unit OFF at discon nect switch es Unit may have multiple power supplies TP Technical Publications Page 1 CAUTION To prevent personal injury or damage to panels unit or structure be sure to observe the following While installing or servicing this unit carefully stow all removed panels out of the way so that the panels will not cause injury to personnel nor cause damage to objects or structures nearby nor will the panels be subjected to damage e g being bent or scratched While handling or stowing the panels consider any weather conditions especially windy conditions that may cause panels to be blown around and bat tered TABLE OF CONTENTS General oh 2 842 ee ieee eae niet aa odie 1 Specifications Electrical Data 2 Application o ns dada 3 Il Unit Components 00 00 00 cece eens 3 Ill Refrigerant System 0 0 c eee eee 13 IM CRarging iste bs accede padded ones A ad Geert a end 14 V Service and Recovery 22 0 005 19 VI Maintenance 2 0000e cece eee 19 VII Diagrams and Sequence of Operation 20 2005 Lennox Industries Inc SPECIFICATIONS General Model No XC21 024 XC21 036 XC21 048 XC21 060 Data Nominal Tonnage kW 2 7 0 3 10 6 4 14 1 5 17 6 Connections Liquid line o d in mm 3 8 9 5 3 8 9 5 3 8 9 5 3 8 9 5 sweat Suction line o d in mm 7 8 22
14. the stationary scroll The liquid is worked toward the center of the scroll and is discharged If the com pressor is replaced conventional Lennox cleanup practic es must be used Due to its efficiency the scroll compressor is capable of drawing a much deeper vacuum than reciprocating com pressors Deep vacuum operation can cause internal fusite arcing resulting in damaged internal parts and will result in compressor failure This type of damage can be detected and will result in denial of warranty claims The scroll com pressor can be used to pump down refrigerant as long as the pressure is not reduced below 7 psig NOTE During operation the head of a scroll compressor may be hot since it is in constant contact with discharge gas The scroll compressors in all XC21 model units are de signed for use with R 410A refrigerant and operation at high pressures Compressors are shipped from the factory with 3MA 32MMMA P O E oil See electrical section in this manual for compressor specifications Page 4 TWO STAGE OPERATION The two stage scroll compressor operates like any stan dard scroll compressor with the exception the two stage compressor modulates between first stage low capacity approximately 67 and second stage high capacity Modulation occurs when gas is bypassed through bypass ports figure 8 bypass ports open in the first suction pock et This bypassing of gas allows the compressor to operate on first stage low c
15. ECT 24VAC A SII IS OPTIONAL LOW AMBIENT SWITCH a NOTE MINIMUM TRANSFORMER REQUIRED IN INDOOR UNIT 40 VA Now Form No 534 862W 2005 Lennos Industries Ine Sequence of Operation NOTE First and second stage cool operate independent of each other and can modulate back and forth according to thermostat demand First Stage Cool low capacity 1 Cooling demand initiates at Y1 in the thermostat 2 Voltage from terminal Y passes through S4 high pressure switch energizes K1 compressor contactor passes through S87 low pressure switch and returns to common side of the 24VAC power Lithe U S A 3 K1 closes energizing compressor B1 and outdoor fan B4 Outdoor fan motor energizes on low speed yellow tap 4 Solenoid L34 is NOT energized so the slider ring remains open limiting compressor to low capacity Second Stage high capacity NOTE Compressor is operating in first stage cool 5 Second stage cool thermostat demand sends voltage to the LSOM After 5 second delay the LSOM converts the AC volt age to DC voltage and energizes solenoid L34 L34 then closes slider ring allowing the compressor to operate on high capacity Variable speed condenser operates on high speed blue tap Page 20
16. a e se ae et e e e 5 A o Stage High Capacity 2 89 ies oo a ee oe JE JHE These are typical pressures only Indoor match up indoor air and indoor load will cause the pressures to vary TABLE 10 R 410A Temperature Pressure Chart Temperature Pressure Temperature Pressure Temperature Pressure Temperature Pressure pS Psig F Psig F Psig F Psig ar e e aso ws so ww so gt E e pe Es ess sides ee FR AI IR Page 18 V SERVICE AND RECOVERY AWARNING Polyol ester POE oils used with R 410A refriger ant absorb moisture very quickly It is very impor tant that the refrigerant system be kept closed as much as possible DO NOT remove line set caps or service valve stub caps until you are ready to make connections A IMPORTANT USE RECOVERY MACHINE RATED FOR R 410A REFRIGERANT If the XC21 system must be opened for any kind of service such as compressor or filter drier replacement you must take extra precautions to prevent moisture from entering the system The following steps will help to minimize the amount of moisture that enters the system during recovery of R 410A 1 Use a regulator equipped nitrogen cylinder to break the system vacuum Do not exceed 5 psi The dry ni trogen will fill the system purging any moisture 2 Remove the faulty component and quickly seal the system using tape or some other means to prevent additional moisture from entering
17. apacity if thermostat demand allows Indoor thermostat setting will determine first or second stage operation The compressor will operate on first stage until demand is satisfied or the indoor temperature reaches the thermostat set point calling for second stage Second stage high capacity is achieved by blocking the bypass ports figure 8 bypass ports closed with a slider ring The slider ring begins in the open position and is con trolled by a 24VDC internal solenoid On a Y2 call the inter nal solenoid closes the slider ring blocking the bypass ports and bringing the compressor to high capacity Two stage modulation can occur during a single thermostat de mand as the motor runs continuously while the compressor modulates from first stage to second stage HOW A SCROLL WORKS US MOVEMENT OF ORBIT SUCTION MRENE a GAS CRESCENT SHAPED GAS POCKET FLANKS 7 ae ORBITING ii SCROLL SUCTIONY POCKET x EALED BY STATIONARY SCROLL CENTRIFUGAL O HIG PRESSURE GAS FORCE SUCTION O DISCHARGE POCKET FIGURE 7 TWO STAGE MODULATION Bypass Ports Closed High Capacity Bypass Ports Open 67 Capacity FIGURE 8 Page 5 TABLE 1 Unit Readings Cooling Operation Y1 Y2 1st Stage Expected Results 2nd Stage Compressor Voltage Same Amperage Higher Condenser Fan motor Amperage Same or Higher Temperature Ambient Same Outdoor C
18. d Remove all power at disconnect be fore removing access panel XC21 units use single pole contac tors Potential exists for electrical shock resulting in injury or death Line voltage exists at all components even when unit is not in operation F Crankcase Heater HR1 and Thermostat The compressor in the unit is equipped with a 70 watt belly band type crankcase heater HR1 prevents liquid from accu mulating in the compressor HR1 is controlled by a thermo stat located on the liquid line When liquid line temperature drops below 50 F the thermostat closes energizing HR1 The thermostat will open de energizing HR1 once liquid line temperature reaches 70 F G Condenser Fan with Variable Speed Motor B4 The condenser fan motor figure 10 used in all units is a three phase electronically controlled d c brushless motor controller converts single phase a c to three phase d c with a permanent magnet type rotor manufactured by GE Be cause this motor has a permanent magnet rotor it does not need brushes like conventional D C motors The motors con sist of a control module and motor Internal components are shown in figure 11 The stator windings are split into three poles which are electrically connected to the controller This ar rangement allows motor windings to be turned on and off in sequence by the controller VARIABLE SPEED CONDENSER FAN MOTOR controller RED ANVLUOdHI FIGURE 10
19. demand signal Y1 is present but compres sor not running 1 Verify Y terminal is connected to 24VAC at contactor coil 2 Verify voltage at contactor coil falls below 0 5VAC when off 3 Verify 24VAC is present across Y and C when thermostat demand signal is present if not present R and C wires are reversed 1 Compressor protector is open 2 Outdoor unit power disconnect is open 3 Compressor circuit breaker or fuse s is open 4 Broken wire or connector is not making contact 5 Low pressure switch open if present in the system Compressor contactor has failed to close Red Trip amp Yellow Alert LEDs Flashing Simultaneous flashing Indicates that the control circuit voltage is too low for operation Yellow Alert Flash Code 1 Long Run Time Compres sor is running extremely long run cycles 1 Low refrigerant charge 2 Evaporator blower is not running 3 Evaporator coil is frozen 4 Faulty metering device 5 Condenser coil is dirty 6 Liquid line restriction filter drier blocked if present 7 Thermostat is malfunctioning Yellow Alert Flash Code 2 System Pressure Trip Discharge or suction pres sure out of limits or compressor overloaded 1 High head pressure 2 Condenser coil poor air circulation dirty blocked damaged 3 Condenser fan is not running 4 Return air duct has substantial leakage 5 If low pressure switch is present see Flash Code 1 information
20. eck for correct voltage at unit unit operating 6 Check amp draw on condenser fan motor NOTE If owner complains of insufficient cooling the unit should be gauged and refrigerant charge checked Refer to section on refrigerant charging in this instruction VII DIAGRAMS OPERATING SEQUENCE A Unit Diagram XC21 024 060 1P 208 230 60 1 s INDICATES OPTIONAL COMPONENTS USE WITH COPPER CONDUCTORS ONLY REFER TO UNIT RATING PLATE FOR MINIMUM CIRDUIT AMPACITY AND MAXIMUM OVERCURRENT PROTECTION SIZE A REFER TO COMPRESSOR IN UNIT FOR ACTUAL TERMINAL ARRANGEMENT A WARNING ELECTRIC SHOCK HAZARD CAN CAUSE INJURY OR DEATH UNIT MUST BE ACCORDANCE WITH NATIONAL AND LOCAL CODES AX REMOVE JUMPER FOR TWO STAGE COOL AX ON A92 CUT ONBOARD W914 JUMPER FROM DS TO R WHEN HUMIDITY CONTROL IS USED AA ON A92 DO NOT CUT ONBOARD W951 JUMPER FROM R TO O IT IS USED FOR APPLICATIONS ONDENSING UNITS LINE VOLTAGE FIELD INSTALLED FOR Ci e CLASS VOLTAGE FIELD INSTALLED ZA FOR CONDENSING UNIT APPLICATIONS USE GE VARIABLE FAN MOTOR B4 R TO O JUMPER REMOVE IN HEAT PUMP APPLICATIONS REMOVE DS TO YI JUMPER WHEN HUMIDITY CONTROL IS USED AGE THERMOSTAT IS USED COOLING UNITS WHEN CONNECT LENNOXo CONDENSING UNITS 4 SECOND STAGE HEAT BULB TO TERMINAL Wes AND REMOVE JUMPER XC21 024 230 01 al XC21 060 230 01 TO COIL TERMI BETWEEN R AND W2 L34 SOLENOID IS LOCATED IN COMPRESSOR COIL IS 24 Gy BO NOT CONN
21. eneral guide and is for use on expansion valve systems only For best results indoor temperature should be 70 F 21 C to 80 F 26 C Monitor system pressures while charging 1 Record outdoor ambient temperature using a digital thermometer 2 Attach high pressure gauge set and operate unit for several minutes to allow system pressures to stabilize 3 Compare stabilized pressures with those provided in table 9 Normal Operating Pressures Minor varia tions in these pressures may be expected due to differ ences in installations Significant differences could mean that the system is not properly charged or that a problem exists with some component in the system Pressures higher than those listed indicate that the system is overcharged Pressures lower than those listed indicate that the system is undercharged A tem perature pressure chart for R 410A refrigerant is pro vided in table 5 for your convenience Verify adjusted charge using the approach method Approach Method 4 Use the same digital thermometer you used to check the outdoor ambient temperature to check the liquid line temperature 5 The difference between the ambient and liquid temper atures should match values given in table 8 If the val ues don t agree with those in table 8 add refrigerant to lower the approach temperature or recover refrigerant from the system to increase the approach tempera ture Be aware of the R 410A refrigerant cyl
22. er the high pressure switch 3 Install high pressure gauge hose onto high pressure switch fitting 4 Turn power on to unit and turn room thermostat to call for cooling 5 Record pressure reading on gauge 6 Remove hose from high pressure fitting and install on liquid line valve 7 Read liquid line valve pressure 8 High pressure fitting pressure liquid line valve pressure filter drier pressure drop 9 If pressure drop is greater than 4 psig replace filter drier See figure 14 10 Re install high pressure switch FIGURE 13 REPLACING FILTER DRIER A S 1 Recover all refrigerant from unit 2 Remove original filter drier 3 Install new filter drier in existing location or alternate location as shown Proper brazing procedures should be followed 4 Evacuate system See section IV part B 5 Recharge system See section IV part C FIGURE 14 Page 10 TABLE 3 Lennox System Operation Monitor LED Troubleshooting Codes Status LED Condition Status LED Troubleshooting Information Green Power LED ON Status LED Description Module has power 24VAC control power is present at the module terminal Green Power LED OFF Module not powering up Determine verify that both R and C module terminals are connected and voltage is present between both terminals Red Trip LED ON System and compressor check out OK Thermostat
23. etail A In order to avoid injury take precaution when lifting heavy objects Removing Installing Louvered Panels IMPORTANT Do not allow panels to hang on unit by top tab Tab is for alignment and not designed to support weight of panel e eS Panel shown slightly ro l tated to allow top tab to exit or enter top slot for removing or instal ling panel a r 7 a SCREW L HOLES ia a r Detail A 0 Detail B Il Unit Components XC21 PARTS ARRANGEMENT CONTACTOR n n a DIY CAPACITOR J WY JDJ tt fi Tin LLL M W WAVUVI 0 LOW PRESSURE SWITCH i COMPRESSOR HIGH PRESSURE SWITCH FIGURE 1 Removing Reinstalling Panels Open the access panels as described in figure 2 y DDYPYU UY EEE e TTT LOL LILIA E SS ROTATE IN THIS DIRECTION __ p gt THEN DOWN TO REMOVE PANEL Access Panel MAINTAIN MINIMUM PANEL ANGLE AS CLOSE TO PARALLEL WITH THE UNIT AS POSSIBLE WHILE INSTALLING PANEL HOLD DOOR FIRMLY TO THE HINGED ANGLE MAY BE TOO oan SIDE TO MAINTAIN EXTREME AAA FULLY ENGAGED TABS uni wil PREFERRED
24. ge valves turn off the vacuum pump and disconnect the manifold gauge center port hose from vacuum pump Attach the manifold center port hose to a nitrogen cylin der with pressure regulator set to 150 psig 1034 kPa and purge the hose Open the manifold gauge valves to break the vacuum in the line set and indoor unit Close the manifold gauge valves A CAUTION Danger of Equipment Damage Avoid deep vacuum operation Do not use compres sors to evacuate a system Extremely low vacuums can cause internal arcing and compressor failure Damage caused by deep vacuum operation will void warranty 7 Shut off the nitrogen cylinder and remove the manifold gauge hose from the cylinder Open the manifold gauge valves to release the nitrogen from the line set and indoor unit 1 Reconnect the manifold gauge to the vacuum pump turn the pump on and continue to evacuate the line set and indoor unit until the absolute pressure does not rise above 500 microns 29 9 inches of mercury within a 20 minute period after shutting off the vacuum pump and closing the manifold gauge valves co 1 When the absolute pressure requirement above has been met disconnect the manifold hose from the vacu um pump and connect it to an upright cylinder of R 410A refrigerant Open the manifold gauge valves to break the vacuum from 1 to 2 psig positive pressure in the line set and indoor unit Close manifold gauge valves and shut off the R 410A cylinder
25. he oth er valves the difference is in the construction These valves are not rebuildable If a valve has failed you must replace it A ball valve is illustrated in figure 17 The ball valve is equipped with a service port with a factory installed Schrader valve A service port cap protects the Schrader valve from contamination and assures a leak free seal valve front seated Ball Valve Valve Closed Use Adjustable Wrench To open rotate Stem Clockwise 90 To close rotate Stem Counter clockwise 90 To indoor coil Use Adjustable Wrench To close rotate Stem Counter clockwise 90 To open rotate Stem BALL Shown Clockwise 90 closed STEM ASS stev e SERVICE a PORT S SCHRADER f VALVE SERVICE PORT CAP To outdoor coil FIGURE 17 IV CHARGING A IMPORTANT The Clean Air Act of 1990 bans the intentional vent ing of CFC s and HFC s as of July 1 1992 Approved methods of recovery recycling or reclaiming must be followed Fines and or incarceration my be levied for noncompliance Units are factory charged with the amount of R 410A refrig erant indicated on the unit rating plate This charge is based on a matching indoor coil and outdoor coil with 15 ft 4 6m line set For varying lengths of line set refer to table 6 for refrigerant charge adjustment TABLE 6 Liquid Line Set Oz per 5 ft grams per 1 5m adjust Diameter from 15 ft 4 6 m line set 3 8 in 3 ou
26. inder It will be light maroon colored Refrigerant should be added through the vapor valve in the liquid state Some R 410A cylinders are equipped with a dip tube which allows you to draw liquid refrigerant from the bottom of the cylinder without turning the cyl inder upside down The cylinder will be marked if it is equipped with a dip tube Page 17 TABLE 8 APPROACH TEMPERATURES Second Stage High Capacity Model No quid Line Outdoor Ambient F C XC21 024 2 5 1 1 48 5 XC21 036 45 1 2 50 5 XC21 048 4 5 1 2 50 5 XC21 060 10 0 1 5 56 5 NOTE For best results the same electronic thermome ter should be used to check both outdoor ambient and liquid line temperatures A IMPORTANT Use table 9 to perform maintenance checks Table 9 is not a procedure for charging the system Minor variations in these pressures may be due to differ ences in installations Significant deviations could mean that the system is not properly charged or that a problem exists with some component in the system A IMPORTANT REFRIGERANT SHOULD BE ADDED THROUGH THE VAPOR VALVE IN THE LIQUID STATE D Oil Charge Refer to compressor nameplate TABLE 9 NORMAL OPERATING PRESSURES Liquid Ion and Suction 5 EEE ee 036 048 air enter ing out door coil oF C First Stage Low Capacity aes speje ee aaa fee eo ar e fo e a EAA 05050 99 15050 155 90 00 559 105 pet
27. it shown 1 With the manifold gauge hose still on the liquid service port and the unit operating stably use a digital ther mometer to record the liquid line temperature 2 At the same time record the liquid line pressure reading 3 Use a temperature pressure chart for R 410A to deter mine the saturation temperature for the liquid line pres sure reading See table 10 S I Subtract the liquid line temperature from the saturation temperature according to the chart to determine sub cooling Saturation temperature Liquid line tem perature Subcooling al 1 Compare the subcooling value with those in table 7 If subcooling is greater than shown recover some refrig erant If subcooling is less than shown add some re frigerant Be aware of the R 410A refrigerant cylinder It will be light maroon colored Refrigerant should be added through the vapor line valve in the liquid state Some R 410A cylinders are equipped with a dip tube that allows you to draw liquid refrigerant from the bottom of the cylinder without turning the cyl inder upside down The cylinder will be marked if it is equipped with a dip tube Page 16 TABLE 7 Subcooling Values for Charging Second Stage High Capacity Satura tion Temp Liquid Line Temp F C XC21 024 7 0 1 3 9 5 Model Number XC21 036 8 2 1 4 56 5 XC21 048 6 0 1 3 33 5 XC21 060 6 0 1 3 33 5 The following procedure is intended as a g
28. mpressor bolts 90 in Ib 10 NM Gauge port seal cap 8 ft Ib 11 NM To Access Schrader Port 1 Remove service port cap with an adjustable wrench 2 Connect gauge to the service port 3 When testing is complete replace service port cap Tighten finger tight then an additional 1 6 turn To Open Service Valve 1 Remove the stem cap with an adjustable wrench 2 Use a service wrench with a hex head extension to back the stem out counterclockwise as far as it will go NOTE Use a 3 16 hex head extension for 3 8 line sizes 3 Replace the stem cap Tighten finger tight then tighten an additional 1 6 turn To Close Service Valve 1 Remove the stem cap with an adjustable wrench 2 Use a service wrench with a hex head extension to turn the stem clockwise to seat the valve Tighten the stem firmly NOTE Use a 3 16 hex head extension for 3 8 line sizes 3 Replace the stem cap Tighten finger tight then tighten an additional 1 6 turn Liquid Line Service Valve Valve Closed Service service port port cap lt gt insert hex indoor coil stem cap to outdoor coil Liquid Line Service Valve Valve Open service port cap Sao service port indoor coil insert hex wrench here Service Port Is Open to outdoor coil To Line Set When Valve Is Closed Front Seated FIGURE 16 Vapor Line Ball Valve All Units Vapor line service valves function the same way as t
29. n as described refer to table 3 to verify the wiring Dis connect power from the compressor and 24VAC power from LSOM Remove the wire from the Y terminal of LSOM and reapply power to the compressor allowing the compressor to run The yellow alert LED will begin flashing a code 8 indicating a welded contactor Dis connect power from the compressor and 24VAC power from the LSOM While the LSOM is off reattach the wire to the Y terminal Reapply power to the compres sor and 24VAC power to the LSOM the yellow alert LED will flash the previous code 8 for one minute and then turn off If the yellow LED does not function as de scribed refer to table 3 to verify the wiring Resetting alert codes Alert codes can be reset manually or automatically Manual reset Cycle the 24VAC power to LSOM off and on Automatic reset After an alert is detected the LSOM continues to monitor the compressor and system When if conditions return to normal the alert code is turned off automatically Page 12 IIl REFRIGERANT SYSTEM 4 WARNING R 410A refrigerant can be harmful if it is inhaled R 410A refrigerant must be used and recovered re sponsibly Failure to follow this warning may result in person al injury or death A Plumbing Field refrigerant piping consists of liquid and vapor lines from the outdoor unit sweat connections to the indoor coil flare or sweat connections Use Lennox L15 sweat non flare series line sets as sh
30. nces per 5 feet 9 5 mm 85 g per 1 5 m If line length is greater than 15 ft 4 6 m add this amount If line length is less than 15 ft 4 6 m subtract this amount A Leak Testing After the line set has been connected to the indoor and outdoor units check the line set connections and indoor unit for leaks Page 14 4 WARNING Refrigerant can be harmful if it is inhaled Refrigerant must be used and recovered responsibly Failure to follow this warning may result in personal injury or death A WARNING Fire Explosion and Personal Safety Hazard Failure to follow this warning could result in damage personal injury or death Never use oxygen to pressurize or purge refrigera tion lines Oxygen when exposed to a spark or open flame can cause damage by fire and or an explosion that could result in personal injury or death 4 WARNING Danger of explosion Can cause equipment damage injury or death When using a high pressure gas such as dry nitrogen to pressurize a refrigeration or air conditioning system use a regulator that can control the pressure down to 1 or 2 psig 6 9 to 13 8 kPa Using an Electronic Leak Detector 1 Connect the high pressure hose of the manifold gauge set to the vapor valve service port Normally the high pressure hose is connected to the liquid line port how ever connecting it to the vapor port helps to protect the manifold gauge set from damage caused by high pres sure
31. ning LSOM will not power the solenoid re gardless of the state of Y2 If alert codes 1 or 9 see table 3 appear while the compressor is running LSOM will turn off the solenoid to prevent solenoid damage from overheating conditions L terminal connection The L connection is used to com municate alert codes to the room thermostat On se lected Lennox SignatureStat thermostats a blinking check LED will display on the room thermostat and on select White Rodgers room thermostats an icon on the display will flash Either will flash at the same rate as the LSOM yellow alert LED NOTE ROOM THERMOSTAT WITH SERVICE OR CHECK LIGHT FEATURE The room thermostat may blink the Check or Service LED or it may come on solid Confirm fault by observing and interpreting the code from the LSOM yellow alert LED at the unit Y2 DC Solenoid Connector DC SOL The 24VDC so lenoid which is internal to the compressor will not op erate properly if 24VAC is applied to the compressor solenoid terminals A voltmeter attached to the DC SOL output will measure 4 18 VDC when the sole noid is be energized Installation verification LSOM To verify correct LSOM installation two functional tests can be performed Dis connect power from the compressor and force a ther mostat call for cooling The red trip LED should turn on indicating a compressor trip as long as 24VAC is mea sured at the Y terminal If the red LED does not functio
32. ogether forming concentric spiral shapes figure 6 One scroll remains stationary while the other is allowed to orbit figure 7 Note that the orbiting scroll does not rotate or turn but merely orbits the station ary scroll SCROLL FORM FIGURE 5 CROSS SECTION OF SCROLLS DISCHARGE STATIONARY SCROLL US as X Y NA S SS TIPS SEALED BY A DISCHARGE PRESSURE ORBITING SCROLL FIGURE 6 N dz SSS Y SG A lt IZ Ay aa g AA SSAASSASSSAY SSS IEEE ZEZZ SSASSN IIIIIIIIIIV a SSASAASASS ZZZ IL ZZIZIZE MSS The counterclockwise orbiting scroll draws gas into the out er crescent shaped gas pocket created by the two scrolls figure 7 1 The centrifugal action of the orbiting scroll seals off the flanks of the scrolls figure 7 2 As the orbiting mo tion continues the gas is forced toward the center of the scroll and the gas pocket becomes compressed figure 7 3 When the compressed gas reaches the center it is dis charged vertically into a chamber and discharge port in the top of the compressor The discharge pressure forcing down on the top scroll helps seal off the upper and lower edges tips of the scrolls figure 6 During a single orbit several pockets of gas are compressed simultaneously providing smooth continuous compression The scroll compressor is tolerant to the effects of liquid re turn If liquid enters the scrolls the orbiting scroll is allowed to separate from
33. oil Discharge Air Higher Compressor Discharge Line Higher Indoor Return Air Same Indoor Coil Discharge Air Lower Pressures Suction Vapor Lower Liquid INTERNAL SOLENOID L34 The internal unloader solenoid controls the two stage op eration of the compressor by shifting a slide ring mecha nism to open low capacity or close high capacity two by pass ports in the first compression pocket of the scrolls in the compressor The internal solenoid is activated by a 24 volt direct current solenoid coil The internal wires from the solenoid in the compressor are routed to a 2 pin fusite connection on the side of the compressor shell The external electrical connection is made to the compressor with a molded plug assembly The molded plug receives 24 volt DC power from the LSOM II If it is suspected the unloader is not operating properly check the following A IMPORTANT This performance check is ONLY valid on systems that have clean indoor and outdoor coils proper air flow over coils and correct system refrigerant charge All components in the system must be func tioning proper to correctly perform compressor modulation operational check Accurate measure ments are critical to this test as indoor system load ing and outdoor ambient can affect variations be tween low and high capacity readings STEP 1 Confirm low to high capacity compressor operation Tools required Refrigera
34. own in table 4 or use field fabri cated refrigerant lines Valve sizes are also listed in table 4 TABLE 4 Recommended Line Set XC21 Connections iqui L15 Liquid Vapor Liquid Vapor i i L15 65 024 3 8 in 7 8 in 3 8 in 7 8 in eaten 036 10 mm 22 mm 10 mm 22 mm 4 6 la e a 3 8 in 7 8in 3 8in 7 8in ice ae 048 10 mm 22mm 10 mm 22 mm s 3 8 in 1 1 8 in 3 8 in 1 1 8 in Field 10 mm 29 mm 10 mm 29 mm Fabricated NOTE When installing refrigerant lines refer to Lennox Technical Support Product Applications for assistance In addition be sure to consider the following points Select line set diameters from table 4 to ensure that oil re turns to the compressor Units are designed for line sets of up to fifty feet 15 m for longer line sets consult piping guidelines Size vertical vapor riser to maintain minimum velocity at minimum capacity Valve Size Page 13 B Service Valves The liquid line and vapor line service valves figures 16 and 17 and gauge ports are used for leak testing evacuating charging and checking charge See table 5 for torque re quirements Each valve is equipped with a service port which has a fac tory installed Schrader valve A service port cap protects the Schrader valve from contamination and serves as the primary leak seal TABLE 5 Sheet metal screws 16 in lb Machine screws 10 28 in Ib Co
35. pip ing and compressor parts NOTE This evacuation process is adequate for a new installation with clean and dry lines If excessive mois ture is present the evacuation process may be re quired more than once A IMPORTANT Use a thermocouple or thermistor electronic vacuum gauge that is calibrated in microns Use an instrument that reads from 50 microns to at least 10 000 microns 1 Connect manifold gauge set to the service valve ports e low pressure gauge to vapor line service valve e high pressure gauge to liquid line service valve 2 Connect micron gauge 3 Connect the vacuum pump with vacuum gauge to the center port of the manifold gauge set 4 Open both manifold valves and start the vacuum pump 5 Evacuate the line set and indoor unit to an absolute pressure of 23 000 microns 29 01 inches of mercu ry During the early stages of evacuation it is desir able to close the manifold gauge valve at least once to determine if there is a rapid rise in absolute pressure A rapid rise in pressure indicates a relatively large leak If this occurs repeat the leak testing procedure NOTE The term absolute pressure means the total actual pressure within a given volume or system above the absolute zero of pressure Absolute pres sure in a vacuum is equal to atmospheric pressure mi nus vacuum pressure O 1 When the absolute pressure reaches 23 000 microns 29 01 inches of mercury close the manifold gau
36. rier is designed to re move moisture and foreign matter which can lead to com pressor failure Moisture and or Acid Check Because POE oils absorb moisture the dryness of the system must be verified any time the refrigerant sys tem is exposed to open air A compressor oil sample must be taken to determine if excessive moisture has been introduced to the oil Table 2 lists kits available from Lennox to check POE oils If oil sample taken from a system that has been exposed to open air does not test in the dry color range the filter drier MUST be replaced A IMPORTANT Replacement filter drier MUST be approved for R 410A refrigerant and POE application Foreign Matter Check It is recommended that a liquid line filter drier be replaced when the pressure drop across the filter drier is greater than 4 psig TABLE 2 10N46 Refrigerant Analysis Checkmate RT700 PO 2 3 years room temperature 3 10N45 Acid Test Tubes Checkmate RT750A three pack years refrigerated Checkmate RT751 Tubes three 6 12 months room temperature 2 10N44 Moisture Test Tubes pack years refrigerated Checkmate RT752C Tubes three 2 3 years room temperature 3 74N40 Easy Oil Test Tubes pack years refrigerated 74N39 Acid Test Kit Sporlan One Shot TA 1 PO MEASURING FILTER DRIER PRESSURE DROP 1 Shut off power to unit 2 Remove high pressure switch from fitting next to filter drier A schrader core is located und
37. seals to properly seat Page 6 Compare Y1 readings with Y2 readings in table 1 Some readings should be higher lower or the same If the readings follow what table 1 specifies the compressor is operating and shifting to high capacity as designed If the readings do not follow what table1 specifies continue to step 2 to determine if problem is with external solenoid plug power STEP 2 Confirm DC voltage output on compressor solenoid plug 1 Shut power off to the outdoor unit 2 Insert lead wires from voltmeter into back of the red and black wire plug jack that feeds power to compres sor solenoid coil Set voltmeter to DC volt scale to read DC voltage output from LSOM II plug See figure 9 FIGURE 9 3 Apply a Y1 and Y2 demand from the indoor thermostat to the LSOM II 4 Turn power back on to unit 5 Compressor should cycle ON when Y1 is calling 6 With Y2 calling 5 seconds after compressor cycles ON LSOM II will output 24 volt DC signal to the com pressor solenoid plug Once the solenoid has pulled in the LSOM II will reduce the DC voltage to a pulsating 6 to 18 volt DC output to the solenoid to allow the sole noid to remain energized A IMPORTANT When checking compressor for two stage operation always cycle Y1 to Y2 from terminals on the LSOMII or room thermostat connections DO NOT cycle sec ond stage Y2 of compressor by unplugging the 24VDC solenoid LSOM Il end of plug The LSOM II will
38. the system 3 Do not remove the tape until you are ready to install new component Quickly install the replacement com ponent 4 Evacuate the system to remove any moisture and oth er non condensables The XC21 system MUST be checked for moisture any time the system is opened Any moisture not absorbed by the polyol ester oil can be re moved by triple evacuation Moisture that has been ab sorbed by the compressor oil can be removed by replacing the filter drier A IMPORTANT Evacuation of system only will not remove mois ture from oil Filter drier must be replaced to elimi nate moisture from POE oil Page 19 VI MAINTENANCE AWARNING Electric shock hazard Can cause inju ry or death Before attempting to per form any service or maintenance turn the electrical power to unit OFF at dis connect switch es Unit may have multiple power supplies See section Il for removing access panels Maintenance and service must be performed by a qualified installer or service agency At the beginning of each cooling season the system should be checked as follows 1 Clean and inspect the outdoor coil The coil may be flushed with a water hose Ensure the power is turned off before you clean the coil 2 Condenser fan motor is prelubricated and sealed No further lubrication is needed 3 Visually inspect connecting lines and coils for evidence of oil leaks 4 Check wiring for loose connections 5 Ch
39. tion Monitor POWER LED I DATA OUTPUT a CONNECTOR Zi 25 SPADE CONNECTOR 5 SOLENOID CONNECTOR ALERT LED TRIP LED FIGURE 15 A IMPORTANT This monitor does not provide safety protection The monitor is a monitoring device only and cannot con trol or shut down other devices LED Functions Alert LED green Indicates voltage within the range of 19 28VAC is present at the system monitor connections Alert LED yellow communicates an abnormal system condition through a unique Flash Code the alert LED flashes a number of times consecutively then pauses then repeats the process This consecutive flashing corre lates to a particular abnormal condition Trip LED red indicates there is a demand signal from the thermostat but no current to the compressor is detected by the module Flash code number corresponds to a number of LED flashes followed by a pause and then repeated Trip 8 Alert LEDs flashing simultaneously indicates that the control circuit voltage is too low for operation Reset ALERT flash code by removing 24VAC power from monitor Last ALERT flash code will display for 1 minute af ter monitor is powered on Thermostat Second Stage Cooling The Lennox system operation monitor LSOM requires a two stage room thermostat to operate properly Y2 room thermostat connection While the compressor is not run
40. tion gauge set Digital volt amp meter Electronic temperature thermometer On off toggle switch Higher Procedure 1 Turn main power OFF to outdoor unit 2 Adjust room thermostat set point above heating op eration on heat pump or below cooling operation the room temperature 5 F 3 Remove control access panel Install refrigeration gauges on unit Attach the amp meter to the common black wire wire of the compressor harness Attach thermometer to discharge line as close as possible to the compressor 4 Turn toggle switch OFF and install switch in series with Y2 wire from room thermostat 5 Cycle main power ON 6 Allow pressures and temperatures to stabilize before taking any measured reading may take up to 10 min utes NOTE Block outdoor coil to maintain a minimum of 375 psig during testing 7 Record all of the readings for the Y1 demand on table 1 8 Close switch to energize Y2 demand 9 Allow pressures and temperatures to stabilize before taking any measured reading this may take up to 10 minutes 10 Record all of the readings of Y2 demand on table 1 NOTE On new installations or installations that have shut down for an extended period of time if the com pressor does not cycle from low stage to high stage on the first attempt it may be necessary to recycle the com pressor back down to low stage and back up to high stage a few times in order to get the bypass
41. ttempt a restart The shutdown feature pro vides protection in case of a frozen bearing or blocked fan blade The motor may attempt to start eight times If the motor does not start after the eighth try the controller locks out Reset controller by momentarily turning off main power to unit capacitors to discharge before at tempting to adjust motor speed tap settings Failure to wait may cause personal injury or death Motor Start Up Page 9 BLOWER MOTOR COMPONENTS STATOR WINDINGS FIGURE 11 Troubleshooting If first or second stage thermostat call for cool is present and the variable speed condenser fan motor does not ener gize check voltage at the breaker box If voltage is present do the following 1 Check for 240 volts between the fan motor RED wires 2 Initiate a first stage call for cool Check for 24 volts be tween the fan motor YELLOW wire and fan motor BLACK wire 3 Initiate a second stage call for cool Check for 24 volts between the fan motor YELLOW wire and fan motor BLACK wire then check for 24 volts between the fan motor BLUE wire and fan motor BLACK 1st Stage low capacity 700 rpm RED L1 L2 YELLOW Y1 ov BLACK common 24V Common 2nd Stage High capacity 820 rpm RED L1 L2 YELLOW y1 BLACK common 24V Common FIGURE 12 H Drier A filter drier designed for all XC21 model units is factory installed in the liquid line The filter d
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