581B,C
Table 43—Cooling Service Analysis
PROBLEM | CAUSE | REMEDY |
Compressor and Condenser Fan | Power failure. | Call power company. |
Will Not Start. |
|
|
Fuse blown or circuit breaker tripped. | Replace fuse or reset circuit breaker. | |
| Defective thermostat, contactor, transformer, or | Replace component. |
| control relay. |
|
| 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 tempera- |
|
| ture. |
Compressor Will Not Start | Faulty wiring or loose connections in compres- | Check wiring and repair or replace. |
But Condenser Fan Runs. | sor circuit. |
|
| Compressor motor burned out, seized, or in- | Determine cause. Replace compressor. |
| ternal overload open. |
|
| Defective run/start capacitor, overload, start | Determine cause and replace. |
| relay. |
|
| One leg of | Replace fuse or reset circuit breaker. Determine |
|
| cause. |
Compressor Cycles (Other Than | Refrigerant overcharge or undercharge. | Recover refrigerant, evacuate system, and re- |
Normally Satisfying Thermostat). |
| charge to nameplate. |
| 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 | Determine cause and replace. |
| relay. |
|
| Defective thermostat. | Replace thermostat. |
| Faulty | Replace. |
| Restriction in refrigerant system. | Locate restriction and remove. |
Compressor Operates Continuously. | Dirty air filter. | Replace filter. |
| 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. | Recover refrigerant, evacuate system, and re- |
|
| charge. |
| Condenser coil dirty or restricted. | Clean coil or remove restriction. |
Excessive Head Pressure. | Dirty air filter. | Replace filter. |
| Dirty condenser coil. | Clean coil. |
| Refrigerant overcharged. | Recover excess refrigerant. |
| Air in system. | Recover refrigerant, evacuate system, and re- |
|
| charge. |
| 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. |
Excessive Suction Pressure. | High heat load. | Check for source and eliminate. |
| Compressor valves leaking. | Replace compressor. |
| Refrigerant overcharged. | Recover excess refrigerant. |
Suction Pressure Too Low. | Dirty air filter. | Replace filter. |
| Low refrigerant charge. | Check for leaks, repair, and recharge. |
| Metering device or low side restricted. | Remove source of restriction. |
| Insufficient evaporator airflow. | Increase air quantity. Check filter and replace if |
|
| necessary. |
| Temperature too low in conditioned area. | Reset thermostat. |
| Outdoor ambient below 25 F. | Install |
Evaporator Fan Will Not Shut Off. | Time off delay not finished. | Wait for |
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