Hot water supply device

摘要

A fan for supplying combustion air into a combustion chamber containing a burner and a heat exchanger for hot water supplyA proportional valve provided in the gas supply passage is provided.In a hot water supply device for controlling the number of fan revolutions based on a combustion characteristic line representing a correlation between a predetermined proportional valve current value and a fan rotational speed so as to burn normally in a burnerA fan jamThe amount of gas injected from the burner increased by decreasing the internal pressure of the combustion chamber.Because it may cause incomplete combustionThis is prevented.The exhaust blocking rate is greater than or equal to a predetermined valueIf the proportional valve current value IP is equal to or greater than a predetermined current value Yip close to the upper limit valueThe actual combustion quantity QJ obtained from the heating quantity in the heat exchanger is compared with the designed combustion quantity QS obtained from the proportional valve current value.ReturnsCombustion characteristic lines used to control fan revolutionThe rate of change in the number of fan rotations relative to the proportional valve current value is switched to the modified combustion characteristic lines L1 to L5 set larger than the reference combustion characteristic line L.Diagram