| 摘要 |
<p>PCT No. PCT/N080/00013 Sec. 371 Date Dec. 20, 1980 Sec. 102(e) Date Nov. 24, 1980 PCT Filed Apr. 14, 1980 PCT Pub. No. WO80/02352 PCT Pub. Date Oct. 30, 1980.In a method and an apparatus for regulating the power which is supplied to a heating element (2) in a water heater (1), preferably a reservoir water heater containing water which is to be heated to a certain temperature, the power which is supplied to the heating element for heating the water, is regulated not only in dependence on the temperature of the water (15), but also in dependence on the temperature of the heating element (2, 4), so that the temperature of the element is kept below a predetermined critical value. The temperature of the heating element is measured directly and/or indirectly, and when the temperature of the element is below the critical value and the temperature of the water in the water heater is below the rated value, maximum power can be supplied to the heating element. When the temperature of the element has reached the critical value, but the temperature of the water in the water heater is still below the rated value, the power is regulated so as to keep the temperature of the heating element below the critical value and to minimize the heating period.</p> |
