HEAT TRANSFER UNIT AND BINARY HOT WATER GENERATION DEVICE

PROBLEM TO BE SOLVED: To suppress a liquid-phase refrigerant for air conditioning accumulated in a liquid receiver during a hot water supply single operation accumulating in the liquid receiver when performing an indoor air conditioning operation after stopping the hot water supply single operation, in a binary hot water generation device which can provide both air conditioning and hot water supply.SOLUTION: Between a cascade heat exchanger 340 and a flow regulating valve 410 of a heat transfer unit 400, a liquid receiver 430 is provided for storing a refrigerant for air conditioning. The heat transfer unit includes a communication pipe 440 for communicating the liquid receiver 430 and a suction pipe 160, and a communication pipe opening/closing valve 450 for opening/closing a flow passage of the communication pipe 440. In the case where an air conditioning operation is performed after stopping a hot water supply single operation, the flow regulating valve 410 and a gas pipe opening/closing valve 420 are closed and the communication pipe opening/closing valve 450 is opened. Thereby, the liquid-phase refrigerant for air conditioning accumulated in the liquid receiver 430 during the hot water supply single operation flows in the communication pipe 440 and is recovered in the suction pipe 160, so that the liquid-phase refrigerant does not accumulate in the liquid receiver 430.SELECTED DRAWING: Figure 1 【課題】空調と給湯のいずれも供給可能な二元温水生成装置において、給湯単独運転時に受液器に溜まった液相の空調用冷媒を、給湯単独運転停止後に室内空調運転する際に、受液器に滞留するのを抑制すること。【解決手段】熱伝達ユニット４００のカスケード熱交換器３４０と流量調整弁４１０との間に、空調用冷媒を貯留する受液器４３０を備え、受液器４３０と吸入管１６０とを連通する連通管４４０と、連通管４４０の流路を開閉する連通管開閉弁４５０とを備え、給湯単独運転停止後に空調運転する場合には、流量調整弁４１０およびガス管開閉弁４２０を閉とし、連通管開閉弁４５０を開とすることで、給湯単独運転時に受液器４３０に溜まった液相の空調用冷媒は、連通管４４０を流れて吸入管１６０に回収されるので、受液器４３０に滞留しない。【選択図】図１