To provide a hot water storage type water heater that carries out an operation to reheat bathwater in which wasteful use of energy is avoided.
The hot water storage type water heater includes: a hot water storage tank for storing high-temperature water; a bathtub; a bathtub temperature detector for detecting the temperature of bathwater in the bathtub; a bathwater-reheating heat exchanger provided for heat exchange between the high-temperature water in the hot water storage tank and the bathwater; a human body detector for detecting a person in a bathroom, an illuminance detector for detecting the level of illuminance in the bathroom; a bathtub pump for sending the bathwater to the bathwater-reheating heat exchanger; and a bathwater-reheating pump for sending the high-temperature water in the hot water storage tank to the bathwater-reheating heat exchanger. The bathtub temperature detector is configured to detect the temperature of the bathwater when the illuminance detector detects more than a certain level of illuminance, and the capacity for reheating the bathwater is determined according to the detected temperature by the bathtub temperature detector. Then, when the human body detector detects a person, the reheating of the bathwater is to be initiated based on the determined capacity for reheating.
KADA HIDEO
NAGAO TOMOHIRO
Daisuke Nagano
Kentaro Fujii