Patent ID: 10267539

Abstract:
A vapor compression system comprising a centrifugal compressor (22) having: an inlet (24); an outlet (26); a first impeller stage (28); a second impeller stage (30); and a motor (34) coupled to the first impeller stage and second impeller stage. A first heat exchanger (38) is downstream of the outlet along a refrigerant flowpath. An expansion device (56) and a second heat exchanger (64) are upstream of the inlet along the refrigerant flowpath. A bypass flowpath (120; 320) is positioned to deliver refrigerant from the compressor bypassing the first heat exchanger. A valve (128) is positioned to control flow through the bypass flowpath, wherein: the bypass flowpath extends from a first location (140) intermediate the inlet and outlet to a second location (142; 342) downstream of the first heat exchanger along the refrigerant flowpath.