| 摘要 |
PURPOSE:To improve safety by controlling the photosensitive condition of a photosensor by operating the switch means of signal generating means by a user and controlling a water supply to a heat exchanger via a control circuit. CONSTITUTION:When a hot water outlet knob 18 is set to a plain spout position or a shower position, since a slide switch 30 is moved to a central position or to a right side while interlocking with the hot water outlet knob 18, a prism 27 built in the slide switch 30 is shifted from a position opposed to a light projecting optical fiber bundle 28 and a light receiving optical fiber bundle 29. Therefore, since light emitted from a light emitting element 25 is not re ceived by a photosensitive element 26 without being reflected by the prism 27, a geared motor 9, a solenoid valve 14 and a sparker 16 are supplied with electric power via a control circuit 19, In result, a stop valve 10 is opened, a heat exchanger 4 is supplied with water, a burner 3 is supplied with fuel gas, a sparker 16 is ignited and the combustion of the fuel gas is performed by the burner 3. Thus, there is no fear of generating short circuit or insulation deterioration and an extremely high safety is obtained. |
