Abstract: A method and apparatus for controlling the burning of a solid fuel furnace is disclosed. In a furnace having a burning chamber, a fuel supply mechanism in the form of a rotating grate, a fuel discharge mechanism in the form of a rotating grate located adjacent the rotating grate of the fuel supply mechanism and at least one air blower, the present invention supplies a control mechanism for controlling the operation of the fuel supply and discharge mechanism as well as the blowers in such a manner that fuel is supplied and discharged in an optimum manner. The control mechanism senses the temperature of the combustion gases and the temperature of the load being heated by the furnace. If the temperature of the load is below a predetermined level and a first time period T.sub.1 has not passed since a preceding fuel supply and discharge, the fans are activated but a fuel supply and discharge cycle is not. If the time of the sensing of the low load temperature is below the time T.sub.