| 摘要 |
PURPOSE:To eliminate the need for a complicated work for any type of gas and to enable to perform a smooth ignition in a slow manner, by constituting a device such that a slow ignition circuit is set to a controller for a gas instantaneous hot-water heater with proportional valve, and a proprotional valve is caused to open gradually irrespective of an output of a PID control circuit at an ignition time. CONSTITUTION:If hot water starts to be fed, a water current switch 17 turns on, and a fan 26 actuates, a prepurge is conducted. After prepurging is complete, a gas main plug 22 and an ignition transformer 23 operates, and simultaneously, an output in a specific wave form, which increases gradually, is outputted from a slow ignition circuit to a valve drive circuit irrespective of an output of a PID temperature regulation circuit to conduct an ignition action. After a given time has elapsed, the slow ignition current gradually increases up to a maximum current for slow ignition which operates a valve so that a gas amount, suited to a type of gas having fastest combustion speed, can be supplied. This causes any type of gas always pass through a point where a reliable firing can be conducted, which results in enabling to perform a reliable, slow, and smooth ignition. |
