| 摘要 |
PURPOSE:To economize the electric power by a method wherein a tank is divided into a hot water storage tank part formed above variable capacity heaters utilizing midnight electric power and a solar heat collecting tank part formed below the heaters and the capacities of the heaters are reduced by thermo switches which operate when the hot water temperature of the storage tank part is above the prescribed value. CONSTITUTION:Primary and secondary electric heaters 2 and 3 are provided at the position below which contains nearly 160l of the heat insulated tank 1 having an total inner volume of 460l. The portion above the heaters having the inner volume of nearly 300l serves as the hot water storage tank 4 and the portion below the heaters having the inner volume of nearly 160l serves as the heat collecting tank 5 and a hot water discharge port 6 and a feed water port 7 are respectively provided above and below the heaters. The primary, secondary and tertiary thermo switches 10, 11 and 12 are provided in the tank and constituted to operate to reduce the capacities of the heaters 2 and 3 when the temperatures at the thermo switches exceed the prescribed values. According to the construction described above, when the hot water temperature is high due to the solar heat collected, the capacities of the heaters 2 and 3 can be reduced because a larger drop of t he hot water temperature is allowed until the time of hot water discharge and the power consumption can be economized. |
