| 摘要 |
PURPOSE:To prevent the flame from being spontaneously extinguished by blowing or other operation, and to perform combustion favorably, by slowly decreasing the decreasing rate of the amount of gas, and controlling a gas proportional valve to be slowed down only when the predetermined value of the amount of decrease in the gas is differentiated from the change in the opening of an air flow adjusting apparatus. CONSTITUTION:In an apparatus provided with a proportional control circuit 13 for driving the gas proportional valve 5 in accordance with the difference between the hot water outflow temperature and the set temperature and the air flow adjusting apparatus 8 whose opening can be controlled in accordance with the amount of the gas at the gas proportional valve 5, the air flow adjusting apparatus 8 is provided with a potentiometer 12 as opening detecting means and a circuit 26 for controlling the gas proportional valve 5 to be slowed down when the predetermined value of the change in the amount of the gas at the gas proportional valve 5 is greater than the change in the opening of the air flow adjusting apparatus 8. |
