JPH0459537B

PURPOSE:To detect that a predetermined amount of hot-water, having a proper temperature, is poured and permit pouring of hot-water without failure by a method wherein the temperature of hot-water, supplied from the electric water heater, feed water temperature and the amount of delivered hot-water are detected to operate the reduced amount of hot-water poured into the bathtub. CONSTITUTION:The control device of an electric water heater 10, in which an exothermic body 12 is conducted to heat water in a hot-water reserving tank 11, is provided with a water meter 22, measuring the amount of hot-water from the tank 11, and temperature detectors 21a, 21b at the upper and lower part of the tank 11. In a micro- computer 30, an amount of pouring water operating means 31 operates the reduced amount of using hot-water temperature using the output values of the water meter and the temperature detector and a comparing means 32 compares the reduced amount of using hot-water temperature operated by the means 31 with the amount of required hot-water while an alarm indication control means 33 operates in accordance with the output of the means 32. As a result, the bathtub may be filled with the hot-water of proper temperature without failure.