| 摘要 |
PURPOSE:To avoid frequent starting and stoppage of a preheating mixed combustion apparatus at the time of its low-load operation, by providing a control damper in a passage for supplying combustion air and a plurality of control valves in an internal passage of a fuel supplying electromagnetic pump. CONSTITUTION:When a voltage is applied to a main circuit and an operation starting switch 15 is handled at the time of high-load operation, a water-temperature controller 9 is turned ON and a fan 1 and an electromagnetic pump 6 are set into operation by the function of a combustor controlling means 19, since the temperature of water stored in a water reserving tank of heat exchanger 8 is lowered. Thus, combustion is started in a combustor 7 and the heat exchanger 8 is heated, so that the temperature of water in the tank is raised. Subsequently, when a selector switch 16 for low-load operation is shifted to its LOW position, contacts 17a, 17b are closed through excitation of a relay 17. Resultantly, a damper 18 is closed partially by a motor 10 for reducing the air-flow rate, and at the same time, a solenoid valve 12 is opened for supplying fuel to the combustor 7 via a low-pressure control valve 13. |
