| 摘要 |
PURPOSE:To prevent a solenoid valve from frozen being damaged without driving the valve when it is in a frozen condition by a method wherein in case the solenoid valve adopted to supply water into a heat collecting pipe is driven by a thermosenser, the valve is arranged within a heat collecting casing. CONSTITUTION:The solenoid valve 6 is provided in a low temperature water supply passage 4 connecting a cistern 1 to the heat collecting pipe of the solar heat hot water boiler and the valve 6 is driven by an electrical signal from the thermosenser 7 provided in the heat collecting casing 21 of the hot water boiler 2 through a control circuit 8. In the above device, the low temperature water supply passage 4 is introduced into the heat collecting casing 21 through the side wall of the latter while the top end of the passage 4 is connected to the starting end of the heat collecting pipe 22 and a solenoid valve 28 is provided at the junction of the passage 4 and the pipe 22. Further, the excitation of an electromagnet 29 of the valve 28 is effected by an electric current through a coil 33 through the action of the thermosenser 7 provided in the terminating end of the heat collecting pipe 22 when the temperature of water in the pipe 22 reaches a predetermined value. Consequently, the driving of the solenoid valve 28 in a frozen condition is avoided. |
