Patent ID: 8695369

Claim:
A heat pump system comprising: a compressor; a first heat exchanger in fluid communication with said compressor; a second heat exchanger in fluid communication with said first heat exchanger and said compressor; a flash tank fluidly coupled to said first heat exchanger and said second heat exchanger; a first conduit extending between said first heat exchanger and said second heat exchanger; and a valve associated with said first conduit and operable in an open state to permit flow along said first conduit between said first heat exchanger and said second heat exchanger to at least partially bypass said flash tank and operable in a closed state to prevent flow along said first conduit between said first heat exchanger and said second heat exchanger to direct flow into said flash tank, wherein the heat pump system is operable in a heating mode and a cooling mode; and wherein said valve is in said open state when the heat pump system is operating in said heating mode and an outdoor ambient temperature is high and is in said closed state when the heat pump system is operating in said heating mode and said outdoor ambient temperature is low.