The controller contains a temperature control with a double thermostat function. The thermostat sensors are placed in the cold air current after the evaporator and in the hot air current right in front of the evaporator, respectively. Not until both thermostats call for refrigeration will the relay operate. When a “night lid” is placed on the appliance the controller will adapt itself to the changed circumstances. Another option is that only the Sout thermostat is selected to be active while the Sin temperature is selected for the display. The controller is available in two versions the extended one of which can coordinate the defrost via wire connections between the controllers.