COMBUSTION CONTROL METHOD IN HOT WATER FEEDER OR BATH FURNACE HAVING HOT WATER FEEDER

PURPOSE:To eliminate an additional boiling by a method wherein a changing set temperature reversely proportion to a detected value of feeding cold water and another detected value of a flow rate of fed-out hot water is calculated, a requisite combustion amount under a feed-forward control, a proportional control and an integral control is calculated in response to the changing set temperature so as to perform an automatic hot water feeding as well as a hot water feeding operation. CONSTITUTION:A required combustion amount is calculated in response to a feed-forward control as well as a proportional control and an integral control in reference to detected information of each of sensors 4, 5 and 11 for sensing a cold water feeding temperature, a hot water feeding temperature and a flow rate of hot water feeding as well as a changing set temperature information having a bath tub set temperature information set by a user corrected. In this case, the changing set temperature is defined by (the bath tub set temperature XKs)/(the cold water feeding temperature X the fed-out hot water flow rate). The feed- forward amount is defined as (the changing set temperature-the cold water feeding temperature) Xthe fed-out water amount X alpha. Thus, the required combustion amount is got in reference to the equation of (the changing set temperature-the fed cold water temperature) X the fed-out hot water flow rate X alpha + (the changing set temperature-the fed-out hot water volume) XKp -SIGMA (the changing set temperature-the fed-out hot water volume) X the fed-out hot water flow rate X Ki. The values of Ks, alpha, Kp and Ki are proportional constants.