Patent ID: 7275385

Claim:
A heat pump system comprising: a first heat exchanger operable to pass refrigerant in a first flow direction and a second flow direction; a second heat exchanger in fluid communication with said first heat exchanger and operable to pass refrigerant in said first flow direction and said second flow direction; a scroll compressor in fluid communication with each of said first and second heat exchangers and operable to compress refrigerant in said first flow direction and said second flow direction; and a fluid circuit including a flash tank and a bypass conduit, said flash tank having an intake conduit and a first outlet conduit in fluid communication with said first and second heat exchangers and operable to deliver sub-cooled-liquid refrigerant to said second heat exchanger in said first flow direction, said bypass conduit disposed between said intake conduit and said first outlet conduit and operable to create a pressure differential between said bypass conduit and said flash tank to prevent flow of sub-cooled liquid refrigerant to said first heat exchanger in said second flow direction.