| 摘要 |
PURPOSE:To prevent hot water temperature and quantity of hot water from being insufficient on completion of heating-up in an actual use condition without spoiling a heat pump cycle, by a method wherein a water temperature detecting part is provided with a plurality of temperature-setting parts, operation is conducted at a low set temperature in a predetermined period in starting a heat source for a heat pump, and the operation is conducted at a high set temperature after the elapse of the predetermined period of time. CONSTITUTION:A water temperature detecting part 12a is so constructed as to stop driving of a relay Ry1 when the temperature detected by a sensor 11 reaches each set temperature of 35 deg.C or 45 deg.C. The characteristics of the heat pump necessitate to circulate water of a temperature of not higher than 35 deg.C to obtain a cycle internal pressure of 21kg/cm<2> at the time of starting, are stabilized after about 10-12min from the starting, and when the temperature of circulated water is gradually raised in proiximity to completion of heating-up in a tank 1 (a temperature approximate to 35 deg.C), the pressure hardly exceeds 21kg/ cm<2> even when water of a temperature of up to about 45 deg.C is circulated. |
