HEAT PUMP AIR CONDITIONER

摘要

A heat pump air-conditioner is provided to perform defrost operation and indoor heating operation at the same time by flowing a part of the refrigerant of high temperature discharged from a compressor to a sub heat-exchanger. A compressor(110) compresses inhaled refrigerant at high pressure and high temperature and discharges the compacted refrigerant. An outdoor heat exchanger(130) and an indoor heat exchanger(120) are connected through the compressor and a pipe. An expansion mechanism(140) is connected between the indoor heat exchanger and the outdoor heat exchanger and decompresses the refrigerant transferred from the indoor heat exchanger or the outdoor heat exchanger. A 4-way valve(150) changes the flow of the refrigerant discharged from the compressor. An accumulator(160) is equipped between the 4-way valve and the compressor and provides the gas refrigerant to the compressor. A sub heat-exchanger(170) performs the heat exchange of the indoor air and the refrigerant. A by-pass unit flows a part of the refrigerant discharged from the compressor to the sub heat-exchanger in defrost operation.