| 摘要 |
PURPOSE:To enhance operating efficiency and to secure required amount of hot water, by making the preset water boiling temperature correspond to the enthalpy of a heat source at the operation limit of the heat pump. CONSTITUTION:A control circuit 24 randomly sets the hot water temperature in a hot water storing tank 6 and controls a heater 17 by turning ON and OFF a contact point 25 in response to the signal from a temperature detector 20. A control circuit 26 opens and closes a contact point 27, which actuates a power relay 23 based on the external air temperatures detected by an air temperature detector 21. The control circuit 26 determines the preset value of the external temperature in correspondence with the preset water boiling temperature. When the air temperature is higher than the preset value and the water temperature at an inlet port of a heat exchanger 3 is lower than the preset value at the time of starting, the contact points 27 and 28 are closed and the power relay 23 is conducted. A current is also conducted through a compressor 2, a blower 18, and a circulating pump 9, and heating is performed by the heat pump. Then, the water temperature at the inlet port of said heat exchanger 3 is detected by a detector 19. When the temperature reaches a preset temp., the contact point 28 is opened, the heat pump 1 and the circulating pump 9 are stopped, and the heater 17 is connected and turned ON and OFF by the signal from the detector 20. |
