Patent attributes
A method and apparatus for controlling the defrost cycles of evaporators associated with the compartments of a refrigerator. Defrost heaters associated with each evaporator are turned on and run until either a predetermined maximum defrost temperature is reached for the compartments or until a predetermined maximum run time is reached for each defrost heater. A controller determines a defrost interval based on running times of the freezer defrost heater and the ice maker defrost heater so that the duration of the defrost interval is inversely related to the duration of the running time of the freezer defrost heater and the ice maker defrost heater. The controller also reduces the defrost interval for every second a door of the compartments remains open, compares the reduced defrost interval with the defrost length, and selects the shorter one as the new defrost interval.
