PROBLEM | CAUSE | REMEDY |
System noises. | Piping vibration. | Support piping as required, check for loose pipe |
|
| connectors. |
| Expansion valve hissing. | Add refrigerant, check for plugged liquid line |
|
| strainer. |
| Compressor noisy. | Check valve plates for valve noise, replace |
|
| compressor (worn bearings), check for loose |
|
| compressor holddown bolts. |
| Insufficient compressor oil. | Add oil. |
Compressor loses oil. | Leak in system. | Repair leak. |
| Plugged or stuck compressor oil return | Repair or replace. |
| check valve. |
|
| Oil trapping in line. | Check piping for oil traps. |
| Crankcase heaters not energized during | Replace heaters. |
| shutdown. |
|
Frosted suction line. | Expansion valve admitting excess | Adjust expansion valve. |
| refrigerant. |
|
Hot liquid line. | Shortage of refrigerant. | Repair leak and recharge. |
Frosted liquid line. | Receiver shutoff valve partially closed or | Open valve or remove restriction. |
| restricted. |
|
| Restricted catchall. | Replace. |
| Restricted strainer drier. | Replace. |
Frosted expansion valve. | Ice plugging TXV orifice. | Apply hot wet cloth to TXV. |
| Moisture indicated by increase in suction | Install drier. |
| pressure. |
|
| Plugged TXV strainer. | Clean strainer or replace TXV. |
LEGEND |
|
|
TXV — Thermostatic Expansion Valve
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