COMPRESSOR
TROUBLESHOOTING
COMPRESSOR RATTING/TAPPING
If you have a noisy compressor it is due to improper charging of refrigerant. An overcharged compressor can cause rattling. If charged with pure liquid (this will void the warranty), there is a high probability you have bent reed valves and that’s what is causing a tapping sound.
COMPRESSOR NOT ENGAGING
Compressor clutch is not receiving 12 volts. Check mode operations at controls. Pressure switch not allowing to engage due to pressures too high or too low – check pressures.
COMPRESSOR DISPLACEMENT REGULATOR VALVE DEFECTIVE (VARIABLE DISPLACEMENT COMPRESSORS ONLY)
1. Valve blocked by impurities (the evaporator tends to freeze) = recover refrigerant from the system
2. Regulator springs of the valve improperly set = replace the displacement regulator valve located in the compressor rear cover
3. Evacuate the incondensable gases and moisture from the system by letting the vacuum pump run at least 30 minutes
4. Restore the recommended amount of refrigerant to the system as well as any oil recovered together with the refrigerant
COMPRESSOR OVERHEATED
Overheating is most often caused by loss of refrigerant charge. Cool suction side refrigerant returning from the evaporator provides cooling for the compressor. Once the refrigerant charge is lost there is no refrigerant entering the compressor, hence no compressor cooling. Blockages in the system will also prevent cool refrigerant flow to the compressor.
NORMAL CENTER BALL & GEAR SET
OVERHEATED CENTER BALL & GEAR SET
COMPRESSOR CONTAMINATED
There are several types of contamination the most common are:
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• Foreign material like metal chips, dirt and desiccant. Resulting in broken internal compressor components eventually locking up the compressor
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• Moisture from improper evacuation or hose permeation. Moisture will corrode internal parts resulting in failure. Moisture will create higher system pressures or freeze in the expansion device and blocking refrigerant flow.
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• A/C system flush
CLUTCH SLIPPAGE
The compressor clutch is simply two friction surfaces forced together, like a set of brakes. Each time the clutch is engaged some amount heat is generated. If the engagements occur rapidly or the system voltage is to low, excessive heat created will cause failure of bearing seals and or melting of the field coil epoxy .
HANDLING OR IMPACT DAMAGE
Striking, dropping or over torque will result in these types of damage: