| 摘要 |
PURPOSE:To enable performing combustion within the optimum combustion range without fluctuations in a mixing ratio by installing an air pressure detection means to an air blower and a gas pressure detection means to a raw gas pipe, specifying a setting value to these detection means and closing a solenoid valve when the air pressure or the gas pressure runs out of the setting value. CONSTITUTION:A rotary speed detection means R judges the rotary speed of a fan of a blower with an air detection means. A raw gas pipe P is connected to a raw gas inlet 52 of a proportional control valve 2. A solenoid valve E installed to the raw gas pipe P, a governor V installed to the downstream side of the solenoid valve E, a gas pressure switch S installed to the downstream side of the governor are used as a gas pressure detection means. When a setting value is determined and the rotary speed of the fan or the raw gas pressure runs out of the setting value, both the rotary speed detection means R and the pressure switch S close the solenoid valve E. The pressure switch can be used as a combustion air pressure detection means. |
