Table 20 Ð Cooling Service Analysis
PROBLEM | CAUSE | REMEDY | |
Compressor and | Power failure. | Call power company. | |
condenser fan | Fuse blown or circuit breaker tripped. | Replace fuse or reset circuit breaker. | |
will not start. | |||
Defective thermostat, contactor, transformer, | Replace component. | ||
| |||
| control relay or capacitor. |
| |
| 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. | |
Compressor will not start | Faulty wiring or loose connections in compressor | Check wiring and repair or replace. | |
but condenser fan runs. | circuit. |
| |
| Compressor motor burned out, seized, or internal | Determine cause. Replace compressor. | |
| overload open. |
| |
| Defective run/start capacitor, overload, start relay. | Determine cause and replace. | |
| One leg of of | Replace fuse or reset circuit breaker. | |
|
| Determine cause. | |
Compressor cycles | Refrigerant overcharge or undercharge. | Reclaim refrigerant, evacuate system, and recharge | |
(other than normally |
| to nameplate. | |
satisfying thermostat). |
|
| |
Defective compressor. | Replace and determine cause. | ||
| |||
| Insufficient line voltage. | Determine cause and correct. | |
| Blocked condenser. | Determine cause and correct. | |
| Defective run/start capacitor, overload, or start relay. | Determine cause and replace. | |
| Defective thermostat. | Replace thermostat. | |
| Faulty | Replace. | |
| Restriction in refrigerant system. | Locate restriction and remove. | |
Compressor operates | Dirty air ®lter. | Replace ®lter. | |
continuously. |
|
| |
Unit undersized for load. | Decrease load or increase unit size. | ||
| |||
| Thermostat set too low. | Reset thermostat. | |
| Low refrigerant charge. | Locate leak; repair and recharge. | |
| Leaking valves in compressor. | Replace compressor. | |
| Air in system. | Reclaim refrigerant, evacuate system, and recharge. | |
| Condenser coil dirty or restricted. | Clean coil or remove restriction. | |
Compressor makes | Compressor rotating in wrong direction. | Reverse the | |
excessive noise. |
| ||
Excessive head pressure. | Dirty air ®lter. | Replace ®lter. | |
| Dirty condenser coil. | Clean coil. | |
| Refrigerant overcharged. | Reclaim excess refrigerant. | |
| Air in system. | Reclaim refrigerant, evacuate system, and recharge. | |
| Condenser air restricted or air | Determine cause and correct. | |
Head pressure too low. | Low refrigerant charge. | Check for leaks; repair and recharge. | |
| Compressor valves leaking. | Replace compressor. | |
| Restriction in liquid tube. | Remove restriction. | |
| Compressor rotating in wrong direction | Reverse the | |
|
| ||
Excessive suction | High heat load. | Check for source and eliminate. | |
pressure. |
|
| |
Compressor valves leaking. | Replace compressor. | ||
| |||
| Refrigerant overcharged. | Reclaim excess refrigerant. | |
| Compressor rotating in wrong direction. | Reverse the | |
|
| ||
Suction pressure too low. | Dirty air ®lter. | Replace ®lter. | |
| Low refrigerant charge. | Check for leaks; repair and recharge. | |
| Metering device or low side restricted. | Remove source of restriction. | |
| Insufficient evaporator air¯ow. | Increase air quantity. Check ®lter and replace | |
|
| if necessary. | |
| Temperature too low in conditioned area. | Reset thermostat. | |
| Outdoor ambient below 25 F. | Install | |
Evaporator fan | Time off delay not ®nished. | Wait for | |
will not shut off. |
|
|