| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water heater capable of extending a time period when hot water supply is available during power failure. <P>SOLUTION: The water heater includes a power supply circuit 60 that outputs a first electric power P1 based on electric power supplied by a commercial power supply 70 when electric power is supplied from the commercial power supply 70 and outputs a second electric power P2 based on the electric power supplied from a battery 71 when power supply from the commercial power supply 70 is stopped. A controller 50, a fan 16, a gas proportional valve 42 and a water volume servo valve 26 are operated by the electric power output from the power supply circuit 60. The controller 50 sets a target combustion amount of a burner 12 to be equal or lower than a first upper limit combustion amount when operated by the first electric power P1; and sets the target combustion amount of the burner 12 to be equal or lower than a second upper limit combustion amount that is smaller than the first upper limit combustion amount, when operated by the second electric power P2. <P>COPYRIGHT: (C)2013,JPO&INPIT |
