PURPOSE: To prevent the occurrence of non-combustion even when an air pressure is exerted during MIN combustion by a method wherein a lower limit limiter is disposed for an peration amount of proportional control for a combustion fan, and an operation amount of proportional control is prevented from reduction to a value lower than a value set at a limiter.
CONSTITUTION: Running of a combustion 2 is controlled by a number of revolutions control circuit 6 during ordinary combustion but during MIN combustion, control through which regulation to a value lower than a value set at a limiter circuit 5 is effected is rendered ineffective. Namely, during ordinary combustion, a voltage of an input voltage waveform between a - b responding to a waveform between c - d decided by the number of revolutions control circuit 6 is applied on the combustion fan 2 to drive the combustion fan 2 to drive combustion fan 2. However, a phase angle cut width is set to, for example, B at the limiter circuit 5 and even when a signal by means of which a cut width is increased to a value higher than the set cut width is outputted from the number of revolutions control circuit 6 during MIN combustion, the cut width is incapable of being increased to a value higher than B.
| JP2006329547 | GAS HOT AIR HEATER |
| JPH0617748 | [Title of Invention] Fuel Combustion Device and Method |
SAKURAZAWA KIYOSHI
KIMURA SHOJI
| JPH0257817A | 1990-02-27 | |||
| JPS61202011A | 1986-09-06 |
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