A handy reference for analysis of a failed compressor, to aid in finding the cause of failure and take corrective action.
Replacement new or remanufactured compressors fail at four times the rate of original compressors.
Thus indicating that replacement failures are caused by systems problems.
The following mechanically related conditions account for approximately 80% of compressor failures.
Flood Back: Liquid refrigerant returning to the compressor during the running cycle.
Flooded Start: Crank case oil diluted with liquid refrigerant due to off cycle vapour migration.
Liquid Slugging: Liquid refrigerant or excess amounts of oil entering the cylinders during the running cycle.
Excessive Discharge Temperatures: Higher than design superheated discharge gas temperatures.
Compressor Oil Loss: Quantity of oil returning from the system is less than that leaving the compressor
Faulty expansion valve of the compressor may be caused by troubles in the refrigerant system such as faulty or incorrectly adjusted evaporator liquid expansion devices, faulty oil control or condenser troubles: all of which, are indicated by definite symptoms. Then symptoms may be caused by incorrect conditions which must be corrected by a step by step procedure. TABLE 2 is a chart showing various incorrect conditions, their possible causes and corrections.