| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a water heating system capable of stably supplying hot water at a water heating set temperature even if a mixing control valve does not have a nearly linear mixing characteristic. <P>SOLUTION: This water heating system is provided with a solar water heater 10 having a heat storage vessel 14 for storing the pre-heated hot water generated by solar heating and a water heater 20 having a mixing control valve 21 for mixing the pre-heated hot water fed from the heat storage vessel 14 with the low-temperature water when necessary to feed it to a heat exchanger 22. In the mixing control valve 21, opening of the valve is controlled to the target mixing ratio, while computing a mixing ratio and a target mixing ratio, and when the valve is opened to the maximum opening, if the mixing ratio at that time is lower than the preset lowest mixing ratio, the valve is forcibly closed till the mixing ratio reaches the lowest mixing ratio. <P>COPYRIGHT: (C)2004,JPO</p> |
