| 摘要 |
A method of defrosting of a heat exchanger (evaporator) in a vapor compression system including, downstream of a heat exchanger (evaporator) ( 3 ) to be defrosted, at least a compressor ( 1 ), a second heat exchanger (condenser/heat rejecter) ( 2 ), and an expansion device ( 6 ) connected by conduits in an operable manner to form an integral closed circuit. The heat exchanger ( 3 ) to be defrosted is subjected to essentially the same pressure as the compressor's ( 1 ) discharge pressure. Thus, the heat exchanger ( 3 ) is defrosted as the high-pressure discharge gas from the compressor ( 1 ) flows through to the heat exchanger, giving off heat to the heat exchanger ( 3 ). In the circuit, in connection with the expansion device ( 6 ) a first bypass loop 23 with a first valve ( 16 '), is provided. A pressure reducing device ( 6 ') is provided in a second bypass loop in conjunction with a second valve ( 16 ''') disposed downstream of the heat exchanger ( 3 ) being defrosted, whereby the first valve ( 16 ') is open and the second valve ( 16 ''') is closed when defrosting takes place. |
