HEAT PUMP HOT-WATER SUPPLIER

PROBLEM TO BE SOLVED: To cope with the supply of hot-water throughout the year by a heat pump hot-water supplier for carbon dioxide gas, which is narrow in the refrigerant space of a high-pressure side and different in the necessary amount of refrigerant between winter and summer so that stabilized operation is difficult to effect by employing an inexpensive refrigerant cycle. SOLUTION: The heat pump hot-water supplier is provided with a refrigerant control circuit T6 , in which a compressor 1, a gas cooler, a refrigerant heat exchanger 3, a refrigerant expansion valve 4 and an evaporator 5 are connected sequentially through a refrigerant pipeline, an accumulator 7 is arranged in the suction side of the compressor and which is branched on the way of a pipeline from the discharging side of the compressor 1 to the gas cooler and arriving at the downstream of the refrigerant expansion valve from a defrosting solenoid valve 8, to pass water through a counter- flow type gas cooler and raise the temperature of the same. In such a heat pump hot-water supplier, the gas cooler is divided into two sets 2A, 2B and the refrigerant gas side of them are connected in series while the water side of them are connected in series in winter to pass water while a three-way valve 14 for bypassing is provided so that the water is not conducted to flow through the gas cooler 2B of a refrigerant heat exchanger side in summer and the three-way valve is operated to permit the adjustment of a high pressure.