Fuel saving furnace improvement

In a furnace for heating a building, the furnace being of the type having a combustion chamber for a heating flame therein, a substantial amount of normally unoccupied space above the combustion chamber and a flue opening for coupling to a chimney, means for carrying a fluid medium about the walls of said space for receiving through the walls heat from said heating flame for heating said building, and means for causing said heating flame to go "ON" and "OFF" in said combustion chamber in accordance with selected heating needs of said building;

• the improvement comprising the inclusion of refractory type heat absorbing members which are one or more from the group consisting of stones, concrete and lava rock, said heat absorbing members being on trays comprised of rod mesh, one above the other in said normally unoccupied space and positioned in the path of products of combustion from said heating flame and having openings for passage of said products of combustion from said heating flame about said heat absorbing members as said products of combustion pass from said heating flame to said flue opening for thereby reducing loss of heat to said flue opening;
• and said trays are held one above the other in the form of a metal support frame having width, breadth and height dimensions substantially smaller than the corresponding dimensions of said normally unoccupied space above said combustion chamber to provide space for flow of said products of combustion against said walls about the normally unoccupied space above said combustion chamber.