US Patent 9244466 Electronic mixing valve in standard hot water heater

A hot water heater includes a hot water tank having a cold water inlet line and a hot water outlet line, an electronically controlled mixing valve fluid coupled to the cold water inlet line and the hot water outlet line and mixed output line and a controller operatively coupled to the mixing valve. A temperature sensor is operatively coupled to the mixed output line and the controller, the controller being operative in response to the sensor to detect a temperature of the water in the mixed output line, compare a setpoint temperature to the detected temperature of the water in the mixed output line, and regulate a flow of one or both of cold water from the cold water input line and hot water from the hot water output line through the electronically controlled mixing valve to maintain the detected temperature at the setpoint temperature.