Abstract: A gas-fired, condensing mode, hot air furnace has an exhaust passage for carrying the products of combustion from a gas burner to an exhaust flue. A heat exchanger is provided in the exhaust passage for extracting heat from the products of combustion. An air passage is provided for carrying a flow of air over the heat exchanger and a blower causes a flow of air through the air passage. The gas burner is enclosed and fires into the heat exchanger. A fresh air duct communicates with the burner enclosure for admitting fresh air thereto. A condenser is provided in the exhaust passage for removing water from the products of combustion, the condenser being exposed to the air passage. A second blower is provided in the exhaust passage for causing fluid flow therein from the fresh air inlet duct through the enclosure and the exhaust passage to the exhaust flue.

Abstract: A boiler having a downdraft solid fuel firebox with a refractory hearth structure with a plurality of parallel internal conduits forming an internal combustion chamber, a heat exchanger below the firebox connected to the outlet of the internal combustion chamber, an outlet blower connected to the outlet of the heat exchanger and an air inlet valve controllable with the outlet blower to control the induction of air through the boiler for automatic boiler control.

Abstract: An improvement in a condensing furnace where gaseous products of combustion are ducted through fin tube condensers that act to heat incoming air. The improvement involves spraying water into the products of combustion upstream of the fin tube condenser, so that the sprayed water droplets mix intimately with the products of combustion and are thus vaporized. In this manner, the combined water vapor and gaseous combustion products can condense in the fin tube condenser to create a liquid condensate of which the pH is closer to neutral than would have been the case in the absence of the sprayed water.

Abstract: A hot air heat exchanger furnace that uses crop residue as a fuel source is provided for producing the heat required for various purposes, such as the drying of grains, peanuts, soybeans and other materials and for the heating of buildings. The furnace includes a combustion chamber, an upper manifold, a lower manifold, a plenum and a number of exhaust tubes. The exhaust tubes direct the flow of combustion gases from the combustion chamber in a serpentine path in the plenum between the upper and lower manifolds and into a stack. Meanwhile, ambient air passes into the plenum, past the heat transfer surfaces of the combustion chamber and the exhaust tubes as heat transfers to it. Then it passes out of the furnace.

Abstract: A housing is provided defining a closed lower combustion chamber and a closed upper afterburn chamber disposed immediately above the combustion chamber with one marginal portion of the combustion chamber projecting horizontally outwardly beyond the corresponding marginal portion of the afterburn chamber. A combined flue gas and bypass chamber is disposed above the one marginal portion of the combustion chamber and is horizontally registered with the afterburn chamber. Partition structure divides the combined flue gas and bypass chamber into central and remote end portions spaced along the aforementioned one marginal portion and a pair of first ports communicate the remote portions with adjacent underlying upper portions of the combustion chamber, a pair of second ports communicate the remote portions with adjacent portions of the afterburn chamber and third port structure communicates the central portion of the afterburn chamber with the central portion of the combined chamber.

Abstract: An air heater comprises a plurality of passes, each having tube banks built into a gas conduit through which passes a flow of heating gas. It also comprises a plurality of delivery and collecting air ducts series-arranged one above the other. The delivery air ducts adjoin the tube banks of each pass and communicate therewith through outlets. The collecting air ducts adjoin the tube banks of each pass and communicate therewith by means of inlets. The collecting air duct is connected to the delivery air duct, the next-in-order along the flow of air, by means of interconnecting air conduits, which are positioned in the interspaces between the tube banks of each individual pass. Each interconnecting air conduit has an inlet orifice adapted to admit a flow of air passing from the collecting air duct, and an outlet orifice through which a flow of air passes from the interconnecting air conduit into the delivery duct.

Abstract: A warm air furnace including a plenum, a blower, heat exchanger disposed within the plenum and an air distribution chamber. The heat exchanger includes an encasement surrounding a plurality of vertically extending heat exchanger tubes. The tubes are in communication with the plenum and with the air distribution chamber. A fibrous refractory inorganic tubular flame chamber is positioned within the encasement and is partially surrounded by the vertically extending tubes. The tubes are positioned in a generally U-shaped pattern and one of the tubes contacts the flame chamber. The tubes along the sides of the pattern are interconnected by upper and lower side baffles. The baffles are vertically spaced from each other to define exhaust outlets. A rear baffle extends between the tubes along the base of the pattern. A flue extends from the encasement for exhaust of combustion gases.

Abstract: A wood burning furnace includes a combustion enclosure made up of a lower closed generally rectilinear fire box which is defined at an upper portion thereof by a semicylindrical roof dome and a top cylindrical-shape smoke chamber supported on a rearward upright cylindrical smoke conduit and a forward upright smoke conduit, these conduits being supported on the fire box roof dome and open between the smoke chamber and fire box. The combustion enclosure is supported inside of a furnace shell above a fan compartment in that shell. The furnace shell and heating air baffles fastened to it are so constructed as to provide a heating air passage between the combustion enclosure and shell, and a blower in the fan compartment forces air from outside of the shell over the surfaces of the combustion enclosure and out the top of the shell to a location for use of heated air.

Abstract: The specification discloses a fireplace stove in which heat exchange tubes slope upwardly from a sloping rear wall to a sloping front wall of a polygonal body and are open at each end. A door is openable and/or removable from the body to form a fireplace. A door frame has a thermostat controlled damper at its top and outlets to the fire area near in the lower, side portions thereof. A baffle is spaced below the flue outlet and is aligned with the flue outlet.

Abstract: A solid fuel burning system which may be readily combined with a conventional fluid fuel burning furnace in a forced air heating system. The solid fuel burning system comprises, in combination, a draft inducing blower which directs air for combustion into the furnace at a point proximate the burning fuel. Baffle walls are provided which separate the smoke and other products of combustion from the clean air to be heated and a novel heat exchanger comprised of a plurality of elongated tubes provide a relatively large heat transfer surface. The furnace is specifically designed to facilitate periodic cleaning of the interior walls of the heat exchanger where creosote and other products of combustion may accumulate. In addition, the system employs a novel electronic control circuit which is tied in with the room thermostat and with a thermocouple disposed within the solid fuel burning furnace.

Abstract: A furnace shell has a fire pot centrally located therein, the walls of the shell and fire pot being spaced to form a fluid heat transfer chamber therebetween. Heat transfer is effected between the pot and the chamber to heat the fluid medium in the chamber. The shell is located in an interior to be heated, such as a building or home, including mobile and motor homes. An inlet conduit has a first end exteriorly positioned of the building interior and a second end substantially pneumatically sealed from the interior and in fluid communication with the fire pot enclosure to provide combustion supporting fluid exclusively from the exterior. A flue has a first end positioned exteriorly of said interior and a second end positioned in the upper portion of the fire pot enclosure to conduct combustion gases to the exterior. The flue is pneumatically sealed from the interior to prevent combustion gases from entering the interior.

Abstract: In order to improve the efficiency of a heater for heating a fluid using hot products of combustion, a second heat exchanger is connected to a first heat exchanger, the first heat exchanger absorbing primarily radiant heat from the hot products of combustion and the second heat exchanger absorbing primarily convected heat from the hot products of combustion. The hot products of combustion either pass through an array of parallel tubes in the second heat exchanger, or the second heat exchanger is inserted into the end of the first heat exchanger.