Electric water heater

Abstract

The invention relates to an electric water heater consisting of: a heat source (1) for heating water; a discharge device (15) for discharging warm water which is heated and produced by the heat source (1); a temperature setting device (8) for setting the temperature of the warm water discharged from the discharge device (15); a temperature detection device (9) for detecting the temperature of the warm water discharged from the discharge device (15); and a control device (10, 11); where the controller (10,11) calculates the temperature difference between the set temperature set by the temperature setting device (8), and the temperature detected by the temperature detection device (9), and performs proportional-integral (PropoTĨÌonal-Integral-DifferentÌal, P1D) control based on the temperature difference, in which during the time the warm water is discharged from the discharge device (15), if the temperature difference state is less than the predetermined value α continuously for a predetermined time, The control unit (flood, 11) stabilizes the output of the heat source (1) at a constant value. Therefore, the electric water heater can supply warm water with a stable temperature, very close to the set temperature.