| 摘要 |
PROBLEM TO BE SOLVED: To simplify the structure of a connecting section, reduce the weight of component parts, reduce the number of junction parts and improve air- tightness reliability. SOLUTION: One end of a hot water falling pipe 9 is communicated with a water chamber in a circulating pump 5, i.e., a positive pressure section of it, and there is provided a temperature keeping heater 14 arranged at the hot water falling pipe 9. When the hot water falling operation is carried out, hot water flows from the hot water falling pipe 9 into a circulating pump 5, passes from a bath return pipe 4 to a bath heat exchanger 3 and the water is supplied from a bath going-pipe 7 to the bath tub. During circulating and heating operations, a hot water falling valve 11 is closed, the circulating pump 5 is driven and the hot water is supplied from a bath returning pipe 4, a bath heat exchanger 3 and the bath going-pipe 7 to the bath tub. Since a negative pressure is applied to a check valve 10 in the hot water falling pipe 9 during circulating and heating operations, it is possible to perform a positive prevention of reverse- flow of hot water toward the bath heat exchanger at the time of circulation of hot water in the bath. |
