Method of operating a heat pump

Abstract

A method of operating a heat pump having an inside heat exchanger, an outside heat exchanger, a compressor, and valves that control the circulation of a refrigerant such that in one operating mode the inside heat exchanger operates as an evaporator while in the other operating mode it operates as a condenser. When switching from one operating mode to the other operating mode first the compressor is stopped, then the inside heat exchanger and the outside heat exchanger are directly connected via the valves until pressure is equal in both of the heat exchangers. Subsequently the valves are moved back into the positions appropriate for the desired operating mode, and the compressor is restarted.

I claim: 
     
         1 . A method of operating a heat pump having:
 an inside heat exchanger;   an outside heat exchanger;   a compressor; and   valves that control the circulation of a refrigerant such that in one operating mode the inside heat exchanger operates as an evaporator while in the other operating mode it operates as a condenser, the method comprising the steps when switching from one operating mode to the other operating mode of sequentially:   stopping the compressor;   directly connecting the inside heat exchanger and the outside heat exchanger via the valves until pressure is equal in both of the heat exchangers;   moving the valves into the positions appropriate for the desired operating mode; and   restarting the compressor.   
     
     
         2 . The method defined in  claim 1 , wherein the valves include:
 a first valve connected between an output of the compressor and the outside heat exchanger;   a second valve connected between the intake of the compressor and the inside heat exchanger;   a third valve connected between the intake of the compressor and the inside heat exchanger; and   a fourth valve connected between the output of the compressor and the inside heat exchanger.   
     
     
         3 . The method defined in  claim 1 , wherein
 in a cooling mode the first and third valves are open and the second and fourth valves are closed;   in a heating mode the first and third valves are closed and the second and fourth valves are open; and   the inside and outside heat exchanges are directly connected for pressure equalization by opening the first through fourth valves.