Abstract: In a low side hermetic compressor, a small portion of the compressed refrigerant gas is diverted and discharged into the oil sump through an orifice into the upper level of the oil in the sump. This results in a supersaturated solution of refrigerant in oil in the upper level which drives the refrigerant out of the oil, thereby creating froth which provides sound reduction without disturbing the lower level which remains stratified. A check valve is provided for preventing reverse flow while requiring a predetermined pressure differential for diversion.

Abstract: Oil normally having refrigerant gas entrained therein is drawn from a sump. A portion of the oil is returned to the sump to agitate the oil in the sump to enhance gas separation therefrom. The remainder of the oil is subjected to centrifugal separation to remove the entrained refrigerant. The separated refrigerant is vented while the separated oil is fed to the lubrication system where contaminant removal takes place.