| 摘要 |
PURPOSE:To keep high room heating capacity upon defrosting operation and defrost surely to retain comfortable property and reliability. CONSTITUTION:The title device is provided with a heat accumulating tank 10, arranged so as to be capable of effecting heat exchange between a compressor 1, a first bypass circuit 6, bypassing a pressure reducer, and a second bypass circuit 21, whose one end is connected to a pipeline from the discharging side of the compressor 1 to an indoor heat exchanger 3 through a four-way valve 2 while the other end of the same is connected to another pipeline from an outdoor heat exchanger 5 to the suction side of the compressor 1 through the four-way valve 2. A two-way valve 7 is constituted so as to be free of opening and closing the first bypass circuit 6 and another two- way valve 22 is constituted so as to be capable of opening and closing the second bypass circuit 21 while a microcomputer 27 controls the two-way valves 7, 22 in accordance with the detecting values of a temperature sensor 23, detecting the frosting of the outdoor heat exchanger 5, and another temperature sensor 24, detecting the heat accumulating amount of the heat accumulating tank 10, and selects a first defrosting method, wherein the two-way valve 7 is opened and the two-way valve 22 is closed, and a second defrosting method, wherein the two-way valves 7, 22 are opened, whereby defrosting operation is effected. |
