| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water heater capable of adjusting the amount of drainage generated from a sub-heat exchanger. <P>SOLUTION: In this water heater 1, the drainage stored in a drain tank 17 is sucked by a drain pump 20, and jetted into a spray from a nozzle 22. A part of tap water flowing into a first supply pipe 30 can be allowed to flow to a main heat exchanger 9 through a bypass pipe 38 when a level of the drainage in the drain tank 17 becomes higher than an upper limit water level or more to prevent the drainage from being excessively sprayed outside of the device 2. Thus the amount of tap water flowing into the sub-heat exchanger 10 can be reduced, and the generation of drainage in the sub-heat exchanger 10 can be effectively reduced. Further as a solenoid valve 45 is disposed in the bypass pipe 38, latent heat from combustion exhaust can be sufficiently recovered in the sub-heat exchanger 10 by normally closing the bypass pipe 38. <P>COPYRIGHT: (C)2009,JPO&INPIT |
