| 摘要 |
PURPOSE:To widen the range of hot water tapping capability while preventing efficiency at the time of maximum combustion from being lowered and preventing heat-exchanging efficiency from being raised with a reduction in combustion quantity, by a method wherein bypass air taken out from a part between a fan and a flow rate restricting plate is introduced between a burner and a heat exchanger to dilute a combustion gas. CONSTITUTION:Bypass air is taken out from a part between the fan 2 and the flow rate restricting plate 3, is passed through an air governor 15 and a bypass air duct 14, and is introduced between a flame hole plate 9 and the heat exchanger 11 to dilute the combustion gas. The flow rate of bypass air is adjusted by the air governor 15, whereby primary pressure is lowered, and the quantity of bypass air is increased. As a result, even when the combustion quantity is reduced, heat-exchanging efficiency is not raised, so that the range of hot water tapping capability is widened, and hot water supplying capability with wide range of use can be obtained. |
