Compressor Starts, but Motor Cycles Off on Overload Protector

Probable Cause:

Excessive suction pressure.

Excessive discharge pressure.

Tight bearings or mechanical damage in the compressor.

Low line voltage.
Improperly wired.

Defective run capacitor or relays.
Defective overload protector.

Shorted or grounded motor windings.



Install ALCO OPR valve or TEV with MOP.

Unload compressors when starting. Use interval unloaders if present.

Check for mechanical damage, check motor and compressor bearings for temperature, and lubricate motor bearings.

Determine reason and correct.

Find source of error and correct.

Replace overload protector, if in-line, then replace compressor.

Replace compressor-use ALCO liquid/suction line filter-driers and follow cleanup procedure.