Goodman Mfg RT6100004R13 manual Testing Crankcase Heater Optional Item, Testing Defrost Control

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SERVICING

A. If the compressor starts and continues to run, the cause for failure is somewhere else in the system.

B. If the compressor fails to start - replace.

COPELAND COMPRESSOR

03 A 12345 L

YEAR MONTH SERIAL PLANT NUMBER

S-18 TESTING CRANKCASE HEATER (OPTIONAL ITEM)

The crankcase heater must be energized a minimum of four

(4) hours before the condensing unit is operated.

Crankcase heaters are used to prevent migration or accumu- lation of refrigerant in the compressor crankcase during the off cycles and prevents liquid slugging or oil pumping on start up.

A crankcase heater will not prevent compressor damage due to a floodback or over charge condition.

WARNING

Disconnect ALL power before servicing.

1.Disconnect the heater lead in wires.

2.Using an ohmmeter, check heater continuity - should test continuous. If not, replace.

NOTE: The positive temperature coefficient crankcase heater is a 40 watt 265 voltage heater. The cool resistance of the heater will be approximately 1800 ohms. The resistance will become greater as the temperature of the compressor shell increases.

S-21 CHECKING REVERSING VALVE AND SOLENOID

Occasionally the reversing valve may stick in the heating or cooling position or in the mid-position.

When stuck in the mid-position, part of the discharge gas from the compressor is directed back to the suction side, resulting in excessively high suction pressure. An increase in the suction line temperature through the reversing valve can also be measured. Check operation of the valve by starting the system and switching the operation from COOLING to HEATING cycle.

If the valve fails to change its position, test the voltage (24V) at the valve coil terminals, while the system is on the COOLING cycle.

If no voltage is registered at the coil terminals, check the operation of the thermostat an the continuity of the connect- ing wiring from the "O" terminal of the thermostat to the unit.

If voltage is registered at the coil, tap the valve body lightly while switching the system from HEATING to COOLING, etc. If this fails to cause the valve to switch positions, remove the coil connector cap and test the continuity of the reversing valve solenoid coil. If the coil does not test continuous - replace it.

If the coil test continuous and 24 volts is present at the coil terminals, the valve is inoperative - replace it.

S-24 TESTING DEFROST CONTROL

To check the defrost control for proper sequencing, proceed as follows: With power ON; unit not running.

1.Jumper defrost thermostat by placing a jumper wire across the terminals "DFT" and "R" at defrost control board.

2.Connect jumper across test pins on defrost control board.

3.Set thermostat to call for heating. System should go into defrost within 21 seconds.

4.Immediately remove jumper from test pins.

5.Using VOM check for voltage across terminals "C & O". Meter should read 24 volts.

6.Using VOM check for voltage across fan terminals DF1 and DF2 on the board. You should read line voltage (208- 230 VAC) indicating the relay is open in the defrost mode.

7.Using VOM check for voltage across "W2 & C" terminals on the board. You should read 24 volts.

8.If not as above, replace control board.

9.Set thermostat to off position and disconnect power before removing any jumpers or wires.

NOTE: Remove jumper across defrost thermostat before returning system to service.

S-25 TESTING DEFROST THERMOSTAT

1.Install a thermocouple type temperature test lead on the tube adjacent to the defrost control. Insulate the lead point of contact.

2.Check the temperature at which the control closes its contacts by lowering the temperature of the control. Part

# 0130M00009P which is used on 2 and 2.5 ton units should close at 34°F ± 5°F. Part # 0130M00001P which is used on 3 thru 5 ton units should close at 31°F ± 3°F.

3.Check the temperature at which the control opens its contacts by raising the temperature of the control. Part # 0130M00009P which is used on 2 and 2.5 ton units should open at 60°F ± 5°F. Part # 0130M00001P which is used on 3 thru 5 ton units should open at 75°F ± 6°F.

4.If not as above, replace control.

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Contents Service Instructions Table of Contents Important InformationSafe Refrigerant Handling Product Identification Split System Air Conditioners R-22Split System Air Conditioners R-22 Split System Heat Pumps R-22 Product Identification Single Piece Air Handlers Single Piece Air Handlers MBR/MBE Air Handlers 036 036 120 3642 1824 Accessories ASC01CPKF24 CPKF36 CPKF42 CPKF48 CPKF60 CPKF61 Expansion Valve Kits FSK01A Coil Accessories Product Design Condensing UnitProduct Design System Operation HeatingCooling Cycle System Operation Indoor Coil Outdoor Thermostatic Expansion Valve AFE18-60A Control Board DescriptionTroubleshooting Chart COOLING/HP Analysis ChartServicing Table of Contents Checking Voltage Checking Wiring Checking THERMOSTAT, WIRING, and Anticipator3A Thermostat and Wiring Servicing3B Cooling Anticipator 3C Heating AnticipatorChecking Time Delay Relay Testing Coil CircuitChecking Transformer Control Circuit Checking Cycle ProtectorTesting Compressor Contactor Testing FAN RelayChecking Contactor AND/OR Relays Checking Contactor ContactsCopeland Comfort Alert Diagnostics Applies to ASC13 & ASH13Diagnostics Table Red TripHard Start KIT Wiring Testing Capacitor ResistanceChecking Loss of Charge Protector Checking CapacitorTesting Capacitance 15B Capacitance Check16A Checking FAN and Blower Motor Windings PSC Motors 16B Checking FAN and Blower Motor ECM Motors16D ECM CFM Adjustments 16C Checking ECM Motor WindingsChart on Next Chart from Previous Itc h 16E Checking GE X13TM Motors Checking Compressor17A Resistance Test GE X13TM Motor ConnectionsTesting Compressor Windings 17B Ground Test17D Operation Test Compressor Ground TestTesting Crankcase Heater Optional Item Testing Defrost ControlTesting Defrost Thermostat Checking Reversing Valve and Solenoid40 AR*F & MBR Electronic Blowers Time Delay Relay Sequence of OperationAR*F & MBR With Single Stage Condensers AR*F & MBR With Single Stage Heat PumpsAEP* & MBE Electronic Blower Time Delay Relay 41 AEP* & MBE with Single Stage CON Densers41A AEP* & MBE with Single Stage Heat Pumps Electric Heater Optional Item Temperature Rise F @ CFM 61A Checking Heater Limit ControlsLeak Testing Nitrogen or NITROGEN-TRACED 61B Checking Heater Fuse Link Optional Electric HeatersChecking Heater Elements Refrigeration Repair PracticeEvacuation EvacuationCharging Checking Compressor Efficiency An inaccurately charged system will cause future prob- lems105B Thermostatic Expansion Valve Overfeeding UnderfeedingSuperheat Thermostatic Expansion ValvesChecking Subcooling Checking Expansion Valve OperationOvercharge of Refrigerant Checking Restricted Liquid LineNON-CONDENSABLES Compressor BurnoutSuction Line Drier Clean-Up Method Refrigerant PipingInstallation Requirements Reversing Valve Replacement System ChargingAIR Handler External Static Coil Static Pressure DropTotal External Static Static Pressure DropALL Fuel System Control Board AFE18-60A Accessories Wiring DiagramsALL Fuel System AFE18-60A Control Board 10kw and Below, One Stage Electric Heat OT/EHR18-60 #2 GRD PLM PLF XFMR-R XFMR-C After Installing Optional Heat KIT, Mark AN X Provided Above HKR Heat Kit GRD PLM PLF Accessories Wiring Diagrams
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