To prevent hot water from being mixed with fed water and provide an effective utilization of solar heat by a method wherein a main valve section is set to be opened in response to a water discharging amount of a larger flow rate than an amount of collected hot water and a sub-valve section is also set to be opened under an amount of discharged water where a water flowing state fed through a lower communicating pipe into a lower section of a main tank section is not disturbed.
As a required amount of hot water is being taken out of a hot water taking-out section 13, a water level in a tank main body 7 at a main tank section 4 is lowered, a float 46 in a sub-valve section 21 at a ball tap 19 acting as a water supplying valve 5 of the water supply tank main body 8 is also lowered in correspondence with the lowering of the water level. Then, the sub-valve guide is moved downward, the sub-valve disk is moved away from the sub-discharging hole and opened, thereby water of predetermined flow rate is discharged and supplied. With such an arrangement as above, water flows into the lower section of the tank main body 7 through the lower communication pipe from the water supplying tank main body 8, wherein the water flow is a gradual or slow one without showing any disturbance in the flowing state, resulting in that the hot water in the tank main body 7 is not mixed with the water and a cold water layer is formed at the lower layer side.
SAKURAI SHINJI
ODAJIMA YU
Next Patent: WINDOW STAIN PREVENTIVE DEVICE FOR SOLAR HEAT COLLECTING APPARATUS