| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of a lift of a combustion flame and the generation of the smell thereof by providing a means to operate a blast fan to effect prepurge of the interior of a body for a given time before the starting of combustion of a gas burner only when the starting of operation of heating operation is indicated by an operation switch. SOLUTION: A fan control part 31 controls energization of a fan motor 14 so that a blast fan 3 is run at, for example, the maximum number of revolutions thereof to effect prepurge of the interior of a body case, and this state is continued for a given time. When prepurge is completed, a combustion control part 30 opens solenoid valves 24 and 25 and energizes an electromagnetic proportional valve 26 so as to start combustion of a gas burner at a maximum combustion amount thereof, and further causes the occurrence of spark discharge to an ignition electrode 19. |
