Service manual

13
11. SERVICE PROBLEMS AND POSSIBLE SOLUTIONS
COOLING MODE
Problems
1. Nothing Runs - Cooling Mode
2. IDFM* Runs, No Compressor, No ODFM*
3. IDFM* Runs, ODFM* Runs, No Compressor
4.
IDFM* Runs, Compressor Runs, No ODFM*
5.
Compressor Runs, ODFM* Runs, No IDFM*
6.
Compressor, ODFM*, IDFM* Runs, Insufficient
Cooling
7.
Compressor, ODFM*, IDFM* Runs, Unit Is Heating
While In Cool Mode
Possible Solutions
No A/C Voltage, No 12 VDC, Thermostat, Wiring, P.C.
Board, High Pressure Switch Open
Cooling Freeze Thermister - (Insufficient Indoor Air Flow),
Thermostat, Wiring, Compressor, Contactor, P.C. Board
Insufficient Voltage To Unit, Run Capacitor, Start Device,
Overload, Wiring, Compressor
Run Capacitor, Fan Motor, P.C. Board, Wiring, Fuse On
Motor Black Wire
Thermostat, Run Capacitor, Wiring, Fan Motor, P.C. Board,
Air Flow Restriction, High Ambient Temperature, Undersized
Refrigeration System, Very Little Or No Refrigerant
Charge, Compressor
Thermostat, Wiring, P.C. Board, Reversing Valve
HEATING MODE
Problems
1. Nothing Runs - Heat Mode
2. IDFM* Runs, No Compressor, No ODFM*
3. IDFM* Runs, ODFM* Runs, No Compressor
4. IDFM* Runs, Compressor Runs, No ODFM*
5. Compressor Runs, ODFM* Runs, No IDFM*
6.
Compressor Runs, ODFM* Runs, IDFM* Runs,
Insufficient Heating
7.
Compressor, ODFM*, IDFM*, Unit Is Cooling While
In Heat Mode
Possible Solutions
No A/C Voltage, No 12 VDC, Thermostat, Sub-base, Wiring,
P.C. Board, High Pressure Switch Open
Heating Freeze Thermister, Low Outdoor Ambient
Conditions, Wiring, Compressor, Contactor, P.C. Board
Insufficient Voltage To Unit, Run Capacitor, Start Device,
Overload, Wiring, Compressor
Run Capacitor, Fan Motor, Wiring, P.C. Board, Fuse On
Motor Black Wire
Run Capacitor, Fan Motor, Wiring, P.C. Board
Air Flow Restriction, Low Ambient Temperature, Undersized
Refrigeration System, Very Little Or No Refrigerant
Charge, Compressors
Wiring, P.C. Board, Reversing Valve
* IDFM - Indoor Fan Motor
* ODFM - Outdoor Fan Motor