Patent ID: 9587855
Date: 2017-03-07
CPC Classifications: F24H

Claim:
1. A method for operating a water heater appliance comprising a tank and a heating element to heat water within the tank, the method comprising: measuring a temperature of water within the tank of the water heater appliance at a first time during a time interval; measuring the temperature of water within the tank of the water heater appliance at a second time during the time interval; establishing a temperature drop of water within the tank of the water heater appliance during the time interval, the step of establishing a temperature drop comprising estimating that the volume of heated water within the tank is half a volume of the tank if the temperature drop of water within the tank of the water heater appliance from said step of establishing is greater than a first function of the set temperature t estimating that the volume of heated water within the tank is one-quarter of the volume of the tank if the temperature drop of water within the tank of the water heater appliance from said step of establishing is greater than a second function of the set temperature t activating the heating element to heat water within the tank based on the estimated volume of heated water.