METHOD OF CONTROLLING COMBUSTION RATE OF GAS BURNERS IN INSTANTANEOUS HOT-WATER HEATER

摘要

PURPOSE:To prevent the formation of dew point water by connecting a plurality of water tubes in parallel with the branch point upstream from the heat exchangers and the confluence downstream therefrom and by supplying to a plurality of gas burners necessary fuel gas equally divided in quantity. CONSTITUTION:Service water or the like drawn through a common pipe 9a branches off at a point 10a into water tubes 2a, 2b passed through heat exchangers 1a, 1b respectively. The water is heated in the respective heat exchangers 1a, 1b by heat of combustion from gas burners 4a, 4b, brought together at a confluence 10b, and discharged through a common hot-water supply pipe 9b and from a hot-water outlet 11. To cope with changes in the load for hot water supply, the total of hot water required and the fuel gas necessary for the hot water requirement are equally divided among the respective gas burners 4a, 4b by the control of respective fuel-regulating valves 3a, 3b. It does not occur, therefore, for a heat exchanger with cold water in the water tube to be placed in a hot atmosphere heated by the gas burner in another heat exchanger. Hence the formation of dew point water can be prevented.