| 摘要 |
PURPOSE:To prevent the wear in the pump seal section caused by involving air and improve the durability and safety by changing over the operation of a pump from strong operation to weak operation by the signal of a detector to detect the passing of water which is provided at a section of an automatic supply hot water passing section when the volume of supply hot water into a tank is small. CONSTITUTION:When the supply hot water is used by opening a supply hot water cock 1 during automatic hot water supplying operation, or when the automatic hot water supplying operation is made during the use of hot water, because the hot water flow branches off at the exit section of a heat exchanger 7 for supplying hot water to a supply hot water passage section 8 and passage section 11 for automatic hot water supply, the volume of the hot water to a tank 12 becomes small. Further, when the pressure of the supply water at the entrance to the device is low, the flow rate becomes small in the same way so that a passing water detector 15 outputs the signal of OFF, and the operation of a circulation pump 14 is changed over from strong operation to weak operation. Since as a result the state of operation of the circulation pump 14 is changed over by the volume of the supply hot water to the tank 12 the undesirable operation that the pump 14 is operated with air involved in the water does not occur. When the volume of the supply hot water to the tank 12 is sufficient, the circulation pump 14 does not involve air in the water and it has sufficient capability of carrying water so that the passing water detector 15 outputs the signal of ON and the circulation pump 14 is operated by strong operation. |
