The stove has a fire space including a grid, a rear wall, side walls, a front door and a cover plate. A distribution space has a separating wall, which separates a primary air channel (7), a secondary air channel (6) and an injected air channel (5) at a distance from each other. The wall has an opening (2), which is covered by a pivotable rotary control disk (4). The control disk has recesses and/or openings (11), by which connection of variable cross sections is formed between the distribution space and the channels. The control disk is driven by a motor.