Compressor failure symptoms on heavy equipment air conditioning
How to tell a failing compressor from an electrical fault or a charge problem before parts are ordered.
CALL 069 268 0988Noise and vibration
A rumbling or knocking noise that changes with clutch engagement usually indicates internal wear or bearing damage. A squeal at engagement often points to belt or clutch problems instead.
Pressure signature
Low differential pressure between high and low sides under load suggests a compressor no longer pumping effectively. High head pressure with normal suction usually points to condenser restriction rather than the compressor.
Clutch behaviour
If the clutch does not engage, check supply voltage, relays, fuses, pressure switches and thermostat inputs before condemning the compressor.
After a failure
Flush the system, replace the drier and expansion valve where contamination is suspected, and verify oil quantity. Skipping these steps is the most common reason a replacement compressor fails early.
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