18
Table 6 — Troubleshooting
SYMPTOM
CAUSE
SOLUTION
Compressor and Outdoor
Fan Will Not Start
Power failure.
Call power company.
Fuse blown or circuit breaker tripped.
Replace fuse or reset circuit breaker. Determine root cause.
Defective thermostat, contactor, transformer.
control relay, or capacitor.
Replacement component.
Insufficient line voltage.
Determine cause and correct.
Incorrect or faulty wiring.
Check wiring diagram and rewire correctly.
Thermostat setting too high.
Lower thermostat setting below room temperature.
High pressure switch tripped.
See problem “Excessive head pressure.”
Low pressure switch tripped.
Check system for leaks. Repair as necessary.
Freeze-up protection thermostat tripped.
See problem “Suction pressure too low.”
Compressor Will Not Start
but Outdoor Fan Runs
Faulty wiring or loose connections in compressor
circuit.
Check wiring and repair or replace.
Compressor motor burned out, seized, or internal
overload open.
Determine cause. Replace compressor or allow enough time for
internal overload to cool and reset.
Defective run/start capacitor, overload, start
relay.
Determine cause. Replace compressor or allow enough time for
internal overload to cool and reset.
One leg of 3-phase power dead.
Replace fuse or reset circuit breaker. Determine cause.
Compressor Cycles (Other
Than Normally Satisfying
Thermostat)
Refrigerant overcharge or undercharge.
Recover refrigerant, evacuate system, and recharge to nameplate.
Defective compressor.
Replace and determine cause.
Insufficient line voltage.
Determine cause and correct.
Blocked outdoor coil or dirty air filter.
Determine cause and correct.
Defective run/start capacitor, overload, start
relay.
Determine cause and correct.
Defective thermostat.
Replace thermostat.
Faulty outdoor-fan (cooling) or indoor-fan
(heating) motor or capacitor.
Replace faulty part.
Restriction in refrigerant system.
Locate restriction and remove.
Defective loader plug.
Determine cause and replace.
Compressor Operates
Continuously
Dirty air filter.
Replaced filter.
Unit undersized for load.
Decrease load or increase unit size.
Thermostat set too low (cooling).
Reset thermostat.
Low refrigerant charge.
Locate leak; repair and recharge.
Air in system.
Recover refrigerant, evacuate system, and recharge.
Outdoor coil dirty or restricted.
Clean coil or remove restriction.
Compressor Makes
Excessive Noise
Compressor rotating in the wrong direction.
Reverse the 3-phase power leads as described in Start-Up.
Excessive Head Pressure
Dirty outside.
Replace filter.
Dirty outdoor coil (cooling).
Clean coil.
Refrigerant overcharged.
Recover excess refrigerant.
Air in system.
Recover refrigerant, evacuate system, and recharge.
Condensing air restricted or air short-cycling.
Determine cause and correct.
Head Pressure Too Low
Low refrigerant charge.
Check for leaks; repair and recharge
Compressor scroll plates defective.
Replace compressor
Restriction in liquid tube.
Remove restriction.
Excessive Suction Pressure
High heat load.
Check for source and eliminate.
Compressor scroll plates defective.
Replace compressor.
Refrigerant overcharge.
Recover excess refrigerant.
Suction Pressure Too Low
Dirty air filter (cooling).
Replace filter.
Dirt or heavily iced outdoor coil (heating).
Clean outdoor coil. Check defrost cycle operation.
Low refrigerant charge.
Check for leaks; repair and recharge.
Metering device or low side restricted
Remove source of restriction.
Insufficient indoor airflow (cooling mode).
Increase air quantity. Check filter and replace if necessary.
Temperature too low in conditioned area.
Reset thermostat.
Field-installed filter drier restricted.
Replace.
Outdoor ambient temperature below 25°F
(cooling).
Install low-ambient kit.
Outdoor fan motor(s) not operating (heating).
Check fan motor operation.
Содержание 50HCQ04---12
Страница 85: ...85 APPENDIX E WIRING DIAGRAMS cont Fig B 50HCQA04 A05 Control Wiring Diagram 208 230 1 60 208 230 3 60 460 3 60...
Страница 86: ...86 APPENDIX E WIRING DIAGRAMS cont Fig C 50HCQA04 A05 Control Wiring Diagram 575 3 60...
Страница 87: ...87 APPENDIX E WIRING DIAGRAMS cont Fig D 50HCQ 06 Control Wiring Diagram 208 230 1 60 208 230 3 60 460 3 60...
Страница 88: ...88 APPENDIX E WIRING DIAGRAMS cont Fig E 50HCQ 06 Control Wiring Diagram 575 3 60...
Страница 93: ...93 APPENDIX E WIRING DIAGRAMS cont Fig J 50HCQ 04 05 06 Power Wiring Diagram 208 230 1 60...
Страница 94: ...94 APPENDIX E WIRING DIAGRAMS cont Fig K 50HCQ 04 05 06 Power Wiring Diagram 208 230 3 60...
Страница 95: ...95 APPENDIX E WIRING DIAGRAMS cont Fig L 50HCQ 04 05 06 Power Wiring Diagram 460 3 60...
Страница 96: ...96 APPENDIX E WIRING DIAGRAMS cont Fig M 50HCQ 04 05 06 Power Wiring Diagram 575 3 60...
Страница 97: ...97 APPENDIX E WIRING DIAGRAMS cont Fig N 50HCQA07 Power Wiring Diagram 208 230 3 60 460 3 60 575 3 60...
Страница 98: ...98 APPENDIX E WIRING DIAGRAMS cont Fig O 50HCQD07 Power Wiring Diagram 208 230 3 60 460 3 60 575 3 60...
Страница 99: ...99 APPENDIX E WIRING DIAGRAMS cont Fig P 50HCQ 08 09 Power Wiring Diagram 208 230 3 60 460 3 60 575 3 60...
Страница 100: ...100 APPENDIX E WIRING DIAGRAMS cont Fig Q 50HCQ 12 Power Wiring Diagram 208 230 3 60...
Страница 101: ...101 APPENDIX E WIRING DIAGRAMS cont Fig R 50HCQ 12 Power Wiring Diagram 460 3 60 575 3 60...
Страница 102: ...102 APPENDIX E WIRING DIAGRAMS cont Fig S 50HCQ PremierLink Control Diagram...
Страница 103: ...103 APPENDIX E WIRING DIAGRAMS cont Fig T 50HCQ RTU Open Control Diagram...
