| 摘要 |
PURPOSE:To make reliably the decision of other cocks by a method wherein the decision of other cocks is not made within a preset period of time immediately after the opening or closing actuation of a drop-in valve is finished but it is made after the lapse of the preset period of time. CONSTITUTION:When a starting switch for starting a drop-in operation is turned on, a drop-in valve 9 is opened in a state that a hot water feed faucet is closed or, in other words, other cocks are closed. Water is allowed to pass through a water feed pipe 1, a burner is ignited, and hot water is supplied to a drop-in pipe 32 through a hot-water supply pipe 3 to start the supply of hot water i.e. the dropping-in of hot water into a bathtub 11. A hot water level in the bathtub 11 is detected by a water level sensor 18, and when the hot water level reaches a preset level, the drop-in valve 9 is closed, and the decision of other cocks is made to decide whether the difference between an inflow amount Q1 of water and a drop-in amount Q2 continues in the state of a preset value MoQ or above (Q1-Q2>=MoQ) during a preset period of time t1. In a case where the difference between the inflow amount Q1 of water and the drop-in amount Q2 is less than the preset value MoQ (Q1-Q2<MoQ) in making the decision of other cocks, hot water is not supplied to the hot water feed faucet through a general hot water feed pipe 31, and it is decided that the hot water feed faucet is closed or, in other words, other cocks are closed. The decision is finished by displaying the state in which other cocks are closed. |
