The aggregate consists of a hopper for solid fuel (chip wood, fuel granules, pellets), screw feeder, fire chamber, firefighting unit, control panel. The hopper is cylindrical. A screw feeder housing is a square box welded to a lower part of the hopper. A special rotating flap is mounted on the rolling bearings at the hopper bottom. It is driven by a drive worm. Flap rotation prevents solid fuel sticking in the hopper. There are stands at the bottom with adjusting bolts, allowing leveling of the aggregate. The screw feeder consist of a housing and a screw.