| 摘要 |
PROBLEM TO BE SOLVED: To improve a rising property of a hot water supply temperature at start of hot water supply.SOLUTION: A hot water storage 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 storage tank 2 and supplying the 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 mixture ratio adjusting valve 27 for adjusting a mixture ratio of hot water allowed to flow into the primary side of the hot water supply external heat exchanger 3 and supplied from the recirculation pipe 26 and hot water supplied from the primary side forward pipe 5; and preheating control means 41 for performing preheating operation for controlling the mixture ratio adjusting valve 27 so as to drive the primary side pump 7 during standby of hot water supply and mix hot water supplied from the recirculation pipe 26. |
