GB776999A - Improvements in furnaces or stoves for heating air or the like - Google Patents

Abstract

776,999. Air-heating furnaces. HOARE, J. H. Jan. 24, 1956 [Jan. 26, 1955], No. 2346/55. Class 64(1) In an air heating furnace with a main fan 11 for extracting the heated air and an exhaust fan 15 for the flue gases, a heating space above and at the sides of a central combustion chamber 1 contains nests of tubes through which the air is drawn by the main fan; the air flows in one pass only through tubes grouped to form a hood 4 over the top of the combustion chamber, and in two passes through the remainder of the tubes at the top and sides. The tubes are arranged in three groups 4, 5, 6. In the first or hood group 4, the air flows once through from the front to a chamber 10 at the back. The rest of the air enters the outermost group 5 at the back and passes through front headers 9 to the intermediate group 6, which deliver to the chamber 10, from which the fan 11 draws the air. The chamber 10 has a cold air inlet controlled by a damper. The chamber containing the tubes has four damper-controlled bottom outlets 16 connected by flues to the exhaust fan 15 to equalize the pull. Transverse vertical baffles are arranged in the hot gas space. The bottom of the furnace is heat-insulated by air-tight compartments and may have tubes or ducts for coolant air below the combustion chamber. The latter may contain a firebridge. The sides of the combustion chamber may be made of firebrick or finned cast-iron sections.