Patent ID: 6170286
Filing Date: 2001-01-09
Classification: F25B

Abstract:
A refrigeration chiller comprising:a compressor;a condenser;an expansion device;an evaporator, said compressor, said condenser, said expansion device and said evaporator being connected to form a refrigeration circuit;a lubricant sump;a first line through which lubricant is delivered from said sump to a location in said compressor;apparatus for causing the movement of lubricant from said sump through said first line; anda second line, said second line being in flow communication with a location in said evaporator to which lubricant migrates during chiller operation, said migrated lubricant mixing with liquid refrigerant in said evaporator to form a lubricant-liquid refrigerant mixture, said second line and said first line being disposed in a heat exchange relationship such that lubricant flowing through said first line rejects heat to lubricant-liquid refrigerant mixture in said second line in sufficient quantity to induce the flow of at least a portion of said lubricant-liquid refrigerant mixture through said second line and to said sump in the absence of a pressure differential between said evaporator and said lubricant sump.