Abstract: A furnace using biomass pellets as fuel, comprising a housing arranged on a base, wherein the housing is internally provided with a burning chamber, the bottom of which is provided with a burning grate, and the burning chamber is connected with a primary oxygen supply device; the primary oxygen supply device comprises an oxygen supply cylinder that communicates with the outside, and the bottom end of the oxygen supply cylinder is connected with an oxygen supply pipe II configured to blow air over the burning grate, and a plurality of air outlet holes I is defined in the oxygen supply cylinder.

Abstract: An impinging air duct that comprises one or more ramps disposed within. The ramps direct air entering the duct through columnating orifices, and helps to provide an even flow of air out of the orifices, along the length of the duct. The angle of the ramp and the location of the ramp within the duct can be adjustable.

Abstract: A biomass stove includes a housing enclosing a firebox that defines a ceiling portion opposite a bottom, a firepot disposed within the firebox, an air intake assembly coupled to the firebox, and at least one duct disposed entirely inside the firebox and extending between the ceiling portion of the firebox and the air intake assembly. The duct(s) provide a heat exchanging flow path for ambient air entering the air intake assembly, where the ambient air is heated within the duct(s) prior to exiting through the ceiling portion of the biomass stove.

Abstract: A heat exchange device is disclosed herein to be used in conjunction with a standard fireplace. The heat exchange device is made from a continuous tube fabricated into loops that surround the burning fuel. The ambient room air, introduced through an opening for air entry into the tube, is blown through the internal lumen of the tube fabricated into loops, the external surfaces of which are in direct contact with burning fuel and flame. The air passing through the internal lumen of the tube fabricated into loops is heated to a high temperature by the burning fuel and flame.

Abstract: A sealed combustion, low profile gas-fired baseboard heater has a heat exchanger which is U-shaped, and which has upper and lower horizontal sections. Appropriate inlets are provided for air and combustion gas, and a gas valve. The air inlet may be coaxial with an exhaust for combustion gases. The heater may include a combustion blower, in which case the heat exchanger can include fins and other features to improve heat transfer. A natural draft version includes a larger bore tubular heat exchanger. Ignition can be by way of a pilot. Alternatively, a hot surface igniter, with safety lockout-timing device, can be used.

Abstract: A space heating unit is designed for use in a recreational vehicle and particularly to operate in conjunction with a cooking stove wherein the heating unit has a housing which is placed over a pair of burners and air flow ducts extend across the housing above the burners to draw air from the room upwardly through the ducts and across the housing in order to heat the air and discharge it into the room. The upper end of the housing communicates with an exhaust duct and has a baffle to regulate the rate of air flow through the housing.

Abstract: A solid fuel burning stove is provided and includes a housing within which a combustion chamber is located. The combustion chamber receives combustion air via an adjustable inlet formed through a channel member running along the base of the housing. The channel member defines a combustion air duct which communicates with a combustion air intake in the rear wall of the housing. Combustion air is drawn into the stove via the air intake and is forced through the combustion air duct by a fan. The combustion air passes through the adjustable inlet into the combustion chamber. A fire box is located within the combustion chamber above the adjustable inlet and holds the solid fuel to be combusted. Hot flue gases heat air flowing through a plurality of heat exchange tubes passing through the combustion chamber. The heated air flowing through the heat exchange tubes is directed into the room in which the stove is located via a plurality of vents in the front wall of the housing.

Abstract: A forced air gas fired heating device may be utilized as a stove insert for a conventional open fireplace or in an alternative embodiment may be formed with a double walled construction for use as a free standing unit. In both embodiments a gas burner adjacent a bottom portion of the housing heats an air space within the housing. A room air inlet conduit traverses back and forth across the heated air space and communicates with an air distribution chamber in an upper portion of the housing. A plurality of room air outlet conduits extend outwardly from the distribution chamber through a front wall of the housing. A heat exchanger is suspended from each of the room air outlet conduits and includes a hollow body portion in fluid communication with the associated air outlet conduit. Each of the heat exchangers has an enclosed longitudinally extending corrugated heat conductive metal plate and terminates in a bottom heat conducted metal plate deposed adjacent the gas burner.

Abstract: A self-contained, free standing, on-demand, woodburning furnace including a firebox (52), including means to force combustion gases through a manifold (68), a hot air gathering plenum and means to selectively force feed the fire (34, 36, 38, 40, 68) and draw heated air from the furnace (8, 10, 12, 14).

Abstract: The heating stove comprises from top to bottom, a smoke space, an oven, a combustion chamber and an ash-pit; a grate separates the chamber from the ash-pit. The grate comprises a plurality of open-ended hollow cylindrical metallic ducts which criss-cross so as to form a X and which open outwardly of the stove for heating ambient air circulating therethrough. Each of the ducts has a substantially-flattened crossing portion, in order to reduce the spacing between the tubes. The grate may support a solid combustible, but permit the ashes to drop into the ash-pit between the ducts. A plurality of upright semi-cylindrical tubes are fixed to the sides of the oven and form passages between the combustion chamber and the smoke space. The oven is heated not only at its bottom but along its side walls and the tubes also serve to heat the ambient air.

Abstract: A self-cleaning, high heat transfer wood or coal stove includes an interior cylindrical squirrel-cage configured fuel grate comprised of parallel air-conducting pipes for heating forced cold air. This arrangement of pipes not only provides for a self-cleaning stove interior due to the cyclical condensation and combustion of deposited effluents produced by combustion, but also greatly enhances the heat transfer capability of the stove by increasing the surface area available for heat exchange. The cyclical condensation and combustion is effected by incrementally rotating the interior cylindrical fuel grate by turning, using a handle inserted into one of a plurality of rod sockets which reside on the front of the stove. The stove of this invention is constructed with separate doors for convenient fuel loading and ash removal, and the fuel loading door is disposed to engage the combustion chamber opening with an air-tight and secure fit.

Abstract: A network of air-heating ducts is inserted between the fire bricks of a stove or fire-place to increase the thermal efficiency of the heating apparatus. Cool air from the room is supplied by an electric fan and a manifold to a first series of U-shaped ducts extending between the fire bricks of the floor and rear wall of the heating apparatus and extending forwardly along the top wall to open within the room at the front of the heating apparatus. When fuel is burning inside the fire-box, hot air exits directly into the room. Another series of air ducts extends from the same manifold between the bricks of the side walls of the heating apparatus and connects with an L-shaped chamber mounted adjacent the rear wall of the apparatus. This chamber feeds hot air to other rooms of the house by an additional electric fan connected across the legs of the L-shaped chamber.

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: A thermostatically actuated arrangement for controlling opening and closing movement of the damper of a wood burning stove includes a duct arrangement extending through the combustion chamber of the stove between an air intake end opening through the stove housing at a location in the lower portion thereof and a discharge end opening through the stove housing at a location upwardly spaced from the intake end, for passage of ambient air through the duct arrangement for radiant heating thereof during burning of wood in the stove to create a continuous convective flow of heated air from the intake end to the discharge end, and a sensitive bimetallic spring disposed to receive the convective air flow from the duct arrangement at its discharge end and operably associated with the damper of the stove for actuating opening and closing movements thereof in response to decreases and increases in the temperature of the airflow.

Abstract: A heat exchange device is adapted to recover heat from the fire box of a wood burning stove or the like for heating ambient air in a room or other enclosed space. The heat exchange device is adapted to mount in a recess in a stove top in place of a lid which is normally supplied with the stove. The device according to the invention includes heat exchange means which extend into the fire box of the stove below the top surface thereof. The heat from the heat exchange device is transmitted into a main cavity of the device where the heat is transferred to air forced through the main cavity by a blower mounted to an outside surface of the device. Air exit means are provided on a surface opposite to the surface on which the blower is mounted to provide a passage for heated air into the room or other enclosed space to be heated. The device may also include a top mounted isolated handle for ease in handling the device such as for moving from one area to another.

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 tight wood burning stove (10) for heating a designated space comprises a housing (12) having an access opening (50) in the front wall (14) thereof and at least one glass panel (64) containing door (54, 56) hingedly mounted on the front wall for closing the opening (50). A latching mechanism (60) on the door (54, 56) engages with undercut flange means (52, 53) surrounding opening (50) for positively maintaining the door (54, 56) in the closed position. A firebrick lined combustion chamber (34) within the housing receives logs through opening (50) for burning and the production of hot combustion gases. An air chamber (48) is formed within the housing (12) in air flow communication with the combustion chamber (34) for feeding air thereto through openings (94, 96) in the air chamber walls (46, 90).

Abstract: A solar rock fireplace, to be connected to a forced air heating system, includes an enclosed heating chamber, a firebox where wood or other combustible material may be burned, a flue extending from the firebox along the length of the heating chamber, and a plurality of solar rocks positioned interiorly of the heating chamber and exteriorly of the firebox and flue. When material is burned in the firebox, the solar rocks are heated. When the air is circulated by the forced air heating system, the air flowing through the heating chamber is heated by the solar rocks.

Abstract: A heating stove has a fire box composed of first and second pluralities of parallel aligned connected vertically oriented curved open-ended conduits lower extremities of the conduits of said first and second pluralities being aligned for contacting a common planar surface to support the stove, with the fire box further being formed by generally planar front and back plates, of substantially the same size and shape, with the front plate having an inlet port therethrough and the back plate having an exhaust port therein. The conduit central portions are largely within the stove fire box. A baffle within the fire box promotes three-pass flow of hot air across the conduit surfaces within the fire box. The first and second pluralities of curved conduits are opposed and in interdigitated engagement. Curved strips separate the curved conduits and thus facilitate stove construction with the conduits in interdigitated engagement.

Abstract: A rectangular stove structure has a stepped top with a sloped intermediate top portion having heated air outlets. Room air is passed through U-shaped ducts arranged along the inside surfaces of the stove side walls, and firebrick is provided on the floor of the stove structure between these ducts. Air is drawn into the ducts through a side opening which may have a blower and conduit associated therewith. The door of the stove has rotary combustion air inlets, and a baffle plate is provided inside the door to provide primary air for the fire, and secondary air for improving air circulation and ventilation inside the stove. Domestic hot water can be heated at the rear of the stove structure in an annular chamber defined for this purpose at the connection for the exhaust gas flue. Domestic hot air can be supplemented by a plenum provided on the lower front top, and the plenum receives heated air from the outlets in the sloped intermediate top portion.

Abstract: A firebox including front, rear and opposite sides interconnected by means of a bottom side at their lower ends and by a top side at their upper ends is provided. Outer rear and bottom walls extend between the rear marginal portions of the opposite sides rearwardly of the rear side and between the lower marginal portions of the opposite sides and the lower marginal edges of the rear wall and the front side below the bottom, respectively, defining a rear to front extending flow passage between the bottom side and wall and a downwardly extending flow passage between the rear side and rear wall. The interior of the firebox includes hollow upper opposite side front to rear extending side manifolds and an upper front transverse manifold extending between and communicated with the forward ends of the side manifolds.

Abstract: An indirect air heater having a single airflow path, the invention provides apparatus capable of discharging large volumes of heated air either toward outdoor work areas or into indoor spaces. The present heater is disposed outdoors, fresh air being taken into the heater and passed in heat exchanging contact with heated combustion products moving in a non-communicating flow within the heater. The heated fresh air is directed toward or into the space to be heated while the combustion products are vented to ambient.

Abstract: This invention comprises a furnace heating device having a fire box and hollow tubing extending longitudinally through the internal portion of said fire box through which a heating medium is circulated to outside radiators. The fire box has an ash drawer extending through the bottom portion of the fire box adjacent to the coiled tubing.

Abstract: A circulating-air, woodburning, heating stove/fireplace combination has a combustion chamber for burning fuel. The back of the stove has an inner wall defining the combustion chamber and a spaced outer back wall forming an air chamber between the two walls. An air inlet is provided at the bottom of the air chamber, and an electric fan or blower is attached to the inlet to force air into the space between the walls at the bottom. This air then passes upwardly in the airspace between the back walls and exits through several parallel heat tubes which extend across the top of the fire chamber. These heat tubes open at the front of the stove, so that the air forced through the airspace by the fan is moved into the room. A baffle is provided above the heat tubes to create turbulence in the combustion products for improving the heat exchange of these products with the air moving through the heat tubes prior to the discharge of the combustion products through a flue located in the top of the stove.

Abstract: Disclosed is a means for heating a space with hot air comprising essentially first and second enclosures, the second enclosure being completely surrounded by and spaced apart from the first enclosure to form an air chamber for the circulation and heating of air. Energy for heating the air is supplied by burning fuel (wood, coal, etc.) disposed on a plurality of spaced apart, grate forming, tubelike members lying in a common plane positioned inside of the second enclosure. A terminal portion of one end of the tubes bridge across the air chamber and the tubes terminal edges are exposed to the space sought to be heated; terminal edges of the other end of the tubes are exposed to and communicate with the air chamber.

Abstract: A wood burning stove for providing heated air to a room or similar area includes a fire chamber, a hearth in the forward portion of the fire chamber, draft inlet means at the front of the fire chamber and a flue at the rear of the fire chamber. Between the hearth and the flue is an enclosed air chamber having front and rear walls; the air chamber communicates at its bottom with the ambient air and at its top with one or more air pipes which extend to the front of the stove and there open to the ambient air. A baffle plate is positioned between and spaced from the air chamber and the flue. Ambient air is heated by passing it through the air chamber and air pipes after they have been heated by hot gases rising from a fire burning on the hearth; the hot gases contact the air pipes and the front wall of the air chamber and, because their normal path of travel to the flue is altered by the baffle plate, contact the rear wall of the air chamber as well.

Abstract: The stove combustion chamber is lined with a layer of refractory material. Above this a baffle extends at an angle upwardly from the rear wall of the stove part way toward its front wall. Three tubular heat exchangers open at their forward ends on a grill on the front of the stove, and extend rearwardly over the combustion chamber and baffle to a duct mounted on the rear of the stove. The refractory material and baffle help retain heat in the stove to keep the heat exchange tubes warm, and a blower, which is connected to the duct and is controlled by a thermostat, blows warm air from inside the tubes outwardly through the grill into the room containing the stove.