| 摘要 |
PURPOSE:To secure the durability and safety of a compressor in winter and ensure the supply of hot-water by a method wherein operation utilizing the heat of reserved hot-water is switched to the operation utilizing atmospheric heat when the outlet water temperature of a water heat exchanger has become higher than a set temperature. CONSTITUTION:An indoor heat exchanger 15 is used as a condenser in case of the rise-up operation of room heating and an outdoor heat exchanger 13 is used as the condenser in case of defrosting operation, further, the water heat exchanger 1 is used as an evaporator at first in case of both said operations. When the outlet water temperature of the water heat exchanger 1 has become the set water temperature t2, lower than a temperature t1, first and second four-way valves 11, 12 and first, second and first, second and third solenoid valves 20, 21, 22 are operated so that the outdoor heat exchanger 13 is operated as the evaporator upon the rise-up operation of room heating while the indoor heat exchanger 15 is operated as the evaporator upon defrosting operation. Then, the circulating pump 2 is stopped. |
