| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hot water supply device of high usability, for elongating service life by shortening an operating time of a heat-retention heater of small output as short as possible, and easily performing maintenance and inspection. <P>SOLUTION: The hot water supply device includes a hot water tank 5, a main heater 15 for heating the water inside, a sub-heater 16 having heat generation amount smaller than that of the main heater 15, and a water temperature control means 40 for controlling the main heater and the sub-heater to keep the water in the hot water tank 5 at a prescribed heat-retention temperature HT, heating the water in the hot water tank 5 by the main heater 15 and the sub-heater 16, and keeping the water in the hot water tank 5 at the heat-retention temperature HT by the sub-heater 16. In the hot water supply device, the water is heated by the main heater 15 and the sub-heater 16 when the water temperature in the hot water tank 5 is a partition temperature ST lower than the heat-retention temperature HT by a respectable degree, or less, power distribution to the sub-heater 16 is cut off when the water temperature reaches the partition temperature ST, and the water in the hot water tank 5 is heated by the main heater 15 until the water temperature reaches the heat-retention temperature HT. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
