| 摘要 |
PURPOSE:To realize water level control without receiving any affection of deterioration with age by a method wherein the water level pressure of a reference point or the connecting port of an additional heating circulation pipeline to a bathtub is detected under a condition that the same pipeline is filled with water upon pouring hot-water while the output correction of a pressure sensor is effected based on the pressure. CONSTITUTION:Upon pouring hot-water to fill a bathtub 1 with hot-water, automatic switches such as a remote controller 35 and the like are put ON to open a hot-water pouring solenoid valve 24. By this action, hot-water, produced at the side of a hot-water supplying heat exchanger 5, enters an additional heating circulation pipeline 14 from a hot-water filling pipe 21 to pour a predetermined amount of priming of a pump into the bathtub 1 from both sides of a returning pipe 15 and a sending pipe 20. When it is detected by a pressure sensor 26 that the additional heating circulation pipeline 14 is filled with hot-water, a circulating pump 18 is driven for a short period of time only, however, hot-water in the bathtub will never be circulated through the additional heating circulation pipeline 14 and the detecting pressure of the pressure sensor 26 upon putting an additional heating switch 16 OFF is set as the water level pressure of a reference point. This pressure is inputted into a correcting unit to effect the pressure correction of the pressure sensor 26. |
