| 摘要 |
PURPOSE:To prevent water in a heat exchanger from being heated and a controller from receiving a bad thermal influence by a method wherein a fan is periodically operated to discharge the heat in a casing outside while a vaporizer is in the wait state for warm-keeping. CONSTITUTION:A combustion air fan 7 is periodically operated during wait period of a vaporizer 5, which is heated for warm-keeping, besides the period of oil burning. That is, while an operating switch is on but hot-water supply is not carried out and is in the wait state, the vaporizer 5 is continuously heated for warm-keeping, and the air fan 7 is periodically operated to send air. The heat in a case, especially in a combustion chamber 2, is discharged outside the case by the periodical air blow, and the outside air flows into the case. Thereby, the residual water in a heat exchanger 4 is prevented from being heated up to a high temperature and a controller 9 is cooled by the outside air. |
