PURPOSE: To perform the most suitable igniting operation in a soft igniting type petroleum hot water feeder during a rotating movement of a burner blower or in the case that a re-ignition is carried out just after an electrical energization is stopped.

CONSTITUTION: An AC power supply 1 of AC100 to 200V is used and a burner blower 2 is electrically energized through a triac 3. During a rotation of the burner blower 2 or in the case that a re-igniting operation is carried out just after an electrical energization is stopped, a triac control circuit 4 controls ON/OFF of the triac 3 and controls to apply a braking against the burner blower 2. With such an arrangement as above, it is possible to reduce an air volume within a short period of time without making any excessive air volume. A soft igniting operation can be started again without deteriorating a characteristic of hot water feeding.