Patent ID: 6880353
Filing Date: 2005-04-19
Classification: F25B,F28D

Abstract:
1. A vapor compression system for use with a carbon dioxide refrigerant, the compression system comprising: a refrigerant circuit having operably coupled thereto, in serial order, a compressor, a first heat exchanger, an expansion device, and a second heat exchanger, a valve disposed within said refrigerant circuit between said first heat exchanger and said expansion device, said valve having a first position and a second position; a defrost circuit defining an inlet and an outlet, said inlet in fluid communication with said refrigerant circuit through said valve, said outlet fluidly coupled to said refrigerant circuit at a position between said valve and said expansion device; a third heat exchanger disposed in said defrost circuit between said inlet and said outlet, said third heat exchanger in thermal exchange with said second heat exchanger, wherein when said valve is in the first position said refrigerant bypasses said defrost circuit and flows to said expansion device without passing through said defrost circuit, and when said valve is in the second position the refrigerant circulates through said defrost circuit wherein thermal energy is removed from the refrigerant in said third heat exchanger and thermal energy is added to said second heat exchanger and wherein when said valve is in second position the refrigerant flows through both said third heat exchanger and said second heat exchanger.