| 摘要 |
PURPOSE:To reduce the number of components of a blower driving device so as to reduce the manufacturing cost of the device by providing an overcurrent limiting circuit which detects the sum of the currents supplied to a first and second blowers and, when the detected sum is larger than a set value, limits the amounts of the currents supplied to the blowers. CONSTITUTION:A fan driving device A is provided with a hot water supplying fan (first blower) 1, hot water supplying fan driving circuit (first blower driving circuit) 2 which controls the amount of the current supplied to the fan 1, bath fan (second blower) 3, bath fan driving circuit (second blower driving circuit) 4 which controls the amount of the current supplied to the fan 3, and overcurrent limiting circuit 5. The circuit 5 detects the sum of the currents supplied to the fans 1 and 3 and, when the detected sum is larger than a set value, limits the amount of the currents supplied to the fans 1 and 3. Therefore, the occurrence of such a trouble that a defective gas water heater is continuously used can be prevented and the safety of the heater can be improved. |
