| 摘要 |
PURPOSE:To meet the convenience of use while improving heating efficiency by a mechanism wherein a hot water pressure detecting switch and a flow switch are mounted to a hot water circuit at the discharge side of a pump in a hot water feed circuit and the pump and a heat source machine are stopped by an OR signal of switching signals from both switches. CONSTITUTION:A relay SP is worked by turning a power switch 8 for making a control circuit ON, and a pump 4 for signals is operated. When all valves 9 of fan convectors 6 are closed, pressure rises up to the cut-off pressure of the signal pump 4. A contact PS of a pressure switch is at OFF because the pressure of hot water exceeds the set pressure of the pressure switch 7 by the pressure rise, hot water does not flow because the valves 9 are closed, and a contact FS of a flow switch is also at OFF. When the valves 9 of the fan convectors 6 ar opened, the pressure of the hot water drops up to value lower than the set value of the pressure switch, the contact PS is at ON, a main pump 3 is worked, and a heat source machine for the hot water starts its operation after the fixed time limit decided by means of a TR. |
