Abstract: A heater stove which fits into a fireplace, the heater stove comprising a cylindrical firebox having (a) a front face, a back face, and a side wall, with a first closed-curve cross-section, extending between the front face and the back face and (b) an axis directed into the fireplace when the heater stove is within the fireplace; an outer cylindrical shell having a side wall with a second closed-curve cross-section and a back wall, the shell surrounding and being spaced apart from the back face and the side wall of the firebox, the side wall of the shell and the side wall of the firebox having a gap therebetween the gap including an opening at the front of the stove; and means for angularly dividing the gap proximate the opening into a plurality of regions which extend a short distance in the axial direction between the firebox side wall and the shell side wall, the regions including at least one lower region into which unheated air is drawn and at least one upper region from which heated air exits, air drawn

Abstract: A cylindrical wood-burning firebox is surrounded by a cylindrical metal outer shell which together comprise a convection heater stove which fits into any of various sizes of fireplaces with the cylinder axes directed into the fireplace. Room air enters the lower front portion of the stove between the firebox and the outer shell, is drawn toward the rear of the heater stove, rises between the firebox and the outer shell as the air is heated by the firebox, and exits as hot air from the upper front of the stove between the firebox and the outer shell. The front face of the firebox is recessed relative to the outer shell. A coil through which a fluid can flow can be provided in the gap between the firebox and the outer shell, said coil having an axis also directed into the fireplace.