| 摘要 |
PURPOSE:To speed up the defrosting and make an apparatus effect an adequate indoor heating by stepping up the speed of revolution of an engine under heating operation and, in the following defrosting, by sending from and indoor heat exchanger the liquid refrigerant heated to a high temperature by the heat-storing operation to an outdoor heat exchanger through a line bypassing a pressure reducer. CONSTITUTION:Detection of frost by a frost sensor 8 which is attached to the surface of an evaporation tube in an outdoor heat exchanger 3 causes an auxiliary engine 10 to run at an increased speed of revolution and the discharge pressure of the refrigerant from a compressor 1 to increase with increase of the speed of its revolution, and the operation results in storage of heat, raising the temperature of the refrigerant flowing through an indoor heat exchanger 5. Simultaneously, the cooling water for the engine is increasingly heated, the high temperature hot water being sent to a hot water heater 14 to heat the indoor space. When the temperature of the refrigerant at the indoor heat exchanger 5, determined by a temperature sensor 9, exceeds a specified point, a bypass valve 7 opens, sending high temperature liquid refrigerant from the indoor heat exchanger 5 through a line bypassing a pressure reducer 4 to the outdoor heat exchanger 3 so that the defrosting is completed in a short time, the frost formed on the outdoor heat exchanger 3 by melting away in a short time under heat of the high temperature refrigerant. |
