| 摘要 |
PURPOSE:To accelerate the rise time of hot water supply by a method wherein heated water is circulated through a hot water storage tank, a first heat exchanger and a second heat exchanger, if the temperature of the water leaving the second heat exchanger exceeds the predetermined temperature. CONSTITUTION:When a cock 30 is open to deliver hot water, the hot water with desired temperature is delivered from the upper part of a hot water storage tank 5 through pipings 31 and 32, if the temperature of the hot water at the upper part of the hot water storage tank 5 exceeds the predetermined third temperature t3 such as 60 deg.C. If the temperature of the hot water at the upper part of the hot water storage tank 5 is below t3, a solenoid valve 11 is open and a solenoid valve 9 is closed. Consequently, the comparatively lower temperature water in the hot water storage tank 5 is led from the lower part of the hot water storage tank 5 to a first heat exchanger 3 and a second heat exchanger 4 so as to be raised its temperature in order to be delivered through a piping 32 as hot water. In such a manner as described above, the hot water with desired temperature can be delivered by heating it for a short time, even when the temperature of the hot water in the hot water storage tank 5 is below the desired temperature. |
