Abstract: A control system for operating a radiant furnace for curing ceramic products, the furnace having a furnace chamber, heating elements for applying radiant energy to the chamber, and movable platform means for supporting the ceramic product to be cured in the chamber. The control system generates a sensor signal responsive to the furnace temperature which is algebraically added to an idle temperature signal, a maximum temperature signal and a ramp signal. The algebraic sum produces an error signal which is applied to a polarity detector for controlling the heating elements in response to a predetermined polarity. The polarity detector is strobed when the sensor signal reaches the maximum temperature signal. Prior to reaching idle temperature the energy to the heating elements is applied in controlled graduated incremental levels. The idle temperature condition is a variable independent of the maximum temperature setting.