Patent attributes
A vapor compression system includes a main circuit comprising a compressor, a condenser, an expansion device and an evaporator serially connected by main refrigerant lines, the compressor having a suction port, a discharge port and an intermediate pressure port; an economizer circuit having an auxiliary expansion device and economizer refrigerant lines connected between said condenser and at least one of said intermediate pressure port and said suction port of said compressor; a bypass circuit having bypass refrigerant lines connected between the intermediate pressure port and the suction port; and a heat exchanger adapted to receive a first flow from the main refrigerant lines and a second flow from at least one of the economizer circuit and the bypass circuit, the first flow and the second flow being positioned for heat transfer relationship within the heat exchanger, wherein the system is selectively operable in a first mode wherein the economizer circuit is active and the bypass circuit is inactive, and a second mode wherein the bypass circuit is active and the economizer circuit is inactive, and wherein the heat exchanger is active for cooling the first flow in both the first mode and the second mode. Further, another system configuration is offered which allows multiple additional important modes of operation as well as enhanced efficiency and reliability and operational envelope expansion through selective valving arrangements.
