ELECTROMAGNETIC INDUCTION TYPE HEATER

PURPOSE:To heat a metallic subject for heating without cooling a switching element so as to enhance heating efficiency by mounting the switching element on the metallic subject for heating via a mounting plate made of an insulating material of high thermal conductivity. CONSTITUTION:A bathing water temperature is inputted to the bathing water temperature detector of a controller for the electromagnetic induction type heater H of e.g. a bathing water circulating and filtering unit. When recognizing the necessity of heating, the control portion 25 outputs a command signal to a switching element 22 to turn on a heating coil 21, for the electromagnetic induction heating of bathing water circulating within a feed water pipe 10. Since the temperature of the element 22 itself rises greatly, the element 22 is mounted on the pipe 10 via a mounting plate 22 made of ceramics or the like and thereby this heat is radiated into the pipe 10 to cool the element 22 and is used effectively in heating the bathing water, thus enabling heating efficiency to be enhanced significantly.