| 摘要 |
<p>PURPOSE:To simplify the constitution of an exhaust gas recirculation system and make the burning equipment small and prevent increased noises by providing a small exhaust gas chamber on the side face of an exhaust gas hood by utilizing the space above the U-tube of a heat exchanger and providing a damper in the small exhaust gas chamber. CONSTITUTION:When water flows with a hot water supply cock opened, the water flow in a water block 19 is detected and a fan 10 is actuated to supply combustion air to a burner 11. Fuel is supplied to the burner 11 in an amount that is determined according to a hot water supply load. The supplied air and fuel are burned by the burner 11 in a combustion chamber 13 and go to a heat exchanger 15. Here, the water that passes through the water block 19 and a water tube 12 is heated by the high temperature exhaust gas in the heat exchanger 15 and used for hot water supply. At this time part of the exhaust gas in an exhaust gas hood 16 enters a small exhaust gas chamber 22 through a through channel 25. After its flow rate is adjusted by a damper 26, it is led to the side of the fan 10 by a through channel 23. And, by making the damper variable the generation of nitrogen oxides is suppressed according to various kinds of fuel and installation aspect of the hot water supplier, and stable combustion is secured.</p> |
