Combustion apparatus

A combustion apparatus comprising:

• a housing accommodating a burner configured to burn combustion gas and a heat exchanger configured to recover heat in combustion exhaust gas generated by the burner to heat water supplied from a water supply source,
• the heat exchanger being disposed below the burner inside the housing, and
• the combustion exhaust gas from the burner being supplied to the heat exchanger from above;
• a combustion fan configured to supply air for combustion of the burner into the housing;
• a post-purge operation-executing section configured to activate the combustion fan for a predetermined period of time after combustion operation of the burner stops;
• an intermittent blower operation-executing section configured to repeat activation and deactivation of the combustion fan a plurality of times at predetermined intervals after the post-purge operation ends;
• a blowing stop operation-executing section configured to stop the intermittent blower operation when a temperature of the heat exchanger becomes lower than a predetermined reference temperature in the intermittent blower operation;
• a first blowing interval-setting section configured to set a deactivation time of the combustion fan to be gradually longer than that at initial deactivation in the intermittent blower operation;
• and
• a first blowing amount-setting section configured to set an activation time of the combustion fan to be gradually shorter than that at initial activation, and/or to set a rotational speed of the combustion fan to be gradually lower than that at the initial activation the intermittent blower operation.