| 摘要 |
PROBLEM TO BE SOLVED: To prevent overshoot of a hot water supply temperature when hot water supply is performed during freezing preventing operation.SOLUTION: A hot water supply type water heater including a hot water supply external heat exchanger 3 for heating secondary side flowing water by hot water allowed to circulate on a primary side and stored in a hot water supply tank and supplying heated hot water further includes: a recirculation pipe 26 branched from a primary side return pipe 6 on a downstream side of a primary side pump 7 and connected to a primary side forward pipe 5 to combine hot water supplied from the downstream of the primary side pump 7 with the primary side of the hot water supply external heat exchanger 3; a switching valve 27 for switching return of hot water flowing out from the primary side pump 7 to the hot water storage tank 2 side or return of the hot water to the primary side inlet 3a side of the hot water supply external heat exchanger 3 through the recirculation pipe 26; and freezing prevention control means 41 which when freezing may occurs, switches the switching valve 27 to the primary side inlet 3a side and drives the primary side pump 7. |
