HEAT PUMP CONTROL SYSTEM

A control system for a heat pump having at least one stage of supplemental heaters, said control system including an electronic thermostat capable of (1) sensing the rate of change of the temperature in the (indoor) conditioned space; and (2) bringing on supplemental heat, following temperature setup of the thermostat, only if the rate of temperature change is below some predetermined value. A suitable time delay can be built into the control to allow the heat pump to stabilize and therefore give a more realistic indication of the ability of the heat pump to handle a given load.