Boilers, commonly called furnaces are devices used for heating homes, shops, offices, halls, factories and other commercial premises. Furnace or boiler with a feeder and a fan controlled by the controller are currently the highest evolutionary form when refferd to manual hand fired boilers. Automatic boilers have not only a much higher level of efficiency when it comes to combustion and performance but are also characterized by a lower solid fuel consumption and offer a better combustion accuracy and output power management. Digital boiler controllers with user applications allows continuous adjustment control, temperature setpoint and modulated boiler power output and high user comfort. The external fuel storage tank (also called solid fuel silo) allows for unattended operation of the boiler reducing the role of the stoker person who uses the furnance or boiler for storage tank refill, periodic cleaning,conservation and ash carrying outt. If comfortable and ecological combustion is a priority the boiler with feeder is the right choice. For these reasons a boiler with a feeder (auger) for fine coal, pellet or biomass is the most ecological and efficient form of solid fuel combustion.