AUTOMATIC BATH HEATER

PURPOSE:To eliminate the change of delivered hot water temperature at the start of delivery and due to the change of flow rate of delivered hot water in use by a method wherein the amount of gas jetted is adjusted by setting the opening of a gas proportioning control valve based upon the water flow rate and temperature respectively measured by a water flow sensor and a temperature, sensor, both of which are arranged in the water inlet pipe of a heat exchanger for hot water supply and further finely adjusted by controlling the opening of the gas proportioning control valve based upon the temperature measured by a temperature sensor arranged in the hot water supplying pipe of said heat exchanger. CONSTITUTION:A service hot water temperature controller 18 sets the opening of a gas proportioning control valve 17 by inputting the water flow rate and the temperature of incoming water respectively measured by a water flow sensor 25 and a temperature sensor 26, both of which are arranged in a water inlet pipe 24 and opens said valve 17 in order to burn gas. At the same time, the signal of the water flow sensor 25 is transmitted through a service hot water controller 7 to a shut-off valve 19 in order to open said valve 9. The temperature of the hot water leaving a heat exchanger 2 for hot water supply is detected by a temperature sensor 16, the signal of which is inputted to a service hot water controller 18 so as to finely adjust the opening of the gas proportioning control valve in order to bring said temperature to a set temperature and to flow the hot water to a hot water supply pipe 5 for bathtub. Furthermore, when the temperature of the water at the outlet of a heat exchanger 10 for a bath detected by a temperature sensor 15 exceeds a set temperature, the signal of said sensor 15 is inputted to a water heating controller 11.