| 摘要 |
PURPOSE:To evacuate the air in a return pipe to enable the water in a bath tab to circulate, by controlling switchover of a three-way valve and on-off operation of a pump in the case a bath tab is located above the pump. CONSTITUTION:Hot water supply to a bath tab 1 is carried out by switching a three- way valve 8 over to the side of a hot water supply device 7, and by operating the hot water supply device 7 and a pump 5. When the water level exceeds the position of an adapter 4 causing a change in the pressure in a return pipe 3, and the signal of a water pressure sensor 9 exceeds a certain level, the hot water supply device 7 and the pump 5 are stopped, and the three-way valve 8 is turned to the side of the return pipe 3. As a result, the hot water in a supply pipe 2 flows back to the return pipe 3 through the pump 5 and the three-way valve 8, and the air in the return pipe 3 is discharged to the bath tab 1 through the adapter 4. The period of time required for replacing the air with water is determined by a delay device 14. After that, a load driving device 11 operates the pump 5 to evacuate the air completely, that is confirmed by a signal from a flow switch 6. Then, after the pump 5 is stopped and the three-way valve 8 is turned to the side of the hot water supply device 7, the hot water supply device 7 and the pump 5 are operated to supply hot water to the bath tab 1. |
