PURPOSE: To remove troubles due to air in a pipeline upon detecting a water level in a bathtub from a hydraulic pressure, and permit stabilized control of the water level by a method wherein the air in the pipeline is excluded by auxiliary feed water when a detected position of water level in the bathtub is lower than a set water level and, thereafter, the water level is detected again to supply hot-water to the set water level in the bathtub.
CONSTITUTION: A water level in a bathtub 2 is detected by a pressure sensor 14 prior to the supply of hot-water and when the detected water level is lower than a set water level hF, water feeding (auxiliary feed water) in the degree capable of excluding air in a pipeline 8 is effected from a hot-water supplier 40 through a pipeline 8 connected to a pressure sensor 14. Next, the water level is detected again by the pressure sensor 14 and when the detected water level is at most the set water level hF, hot-water is supplied into the bathtub 2 until the water level, detected by the pressure sensor 14, becomes the set water level hF. According to this method, troubles due to air in the pipeline 8 upon detecting the water level in the bathtub 2 by a hydraulic pressure can be removed and stabilized water level control can be effected.
WATANABE SETSUO
HIRANO JUNYA
MATSUMURA AKIRA
