Abstract: A system for combusting fuel comprising an apparatus that receives fuel that is characterized as comprising interstitial spacing and wherein oxidants pass through the interstitial spacing of the fuel to sustain a combustion reaction at the interface of a reaction chamber while the byproducts of combustion pass into the reaction chamber.

Abstract: Combustion apparatus for use with a solid fuel has a firebox constructed at least in part of a fired refractory carbide material. The fired refractory carbide material has a catalytic effect on the combustion process providing a cleaner and more efficient combustion. The fired refractory material also absorbs heat from the combustion process directly or indirectly by heat exchange with combustion products and dissipates the absorbed heat over an extended period of time providing space heating after the combustion process is completed.

Abstract: A wood burning furnace providing, in sequential connection, an air box, a fire box with a wood storage box/primary combustion chamber and a secondary combustion chamber separated by an ash grate, a heat exchanger, an exhaust manifold, and a smoke stack. The air box has an input port attached to an intake air blower. The air box also has two dampers, a thermostatically controlled first damper providing controlled access to an updraft exhaust pipe connected to the smoke stack. The second damper provides controlled access to the wood storage box/primary combustion chamber.

Abstract: A method is provided for regulating the output of a solid fuel furnace having primary and secondary combustion chambers arranged adjacent to each other, in particular one above the other or side by side, and are separated from each other by a partition in the floor or wall but are nevertheless connected to each other by at least one partition opening. The secondary combustion chamber is connected through a secondary exhaust-gas channel to a flue-gas passage, and the primary combustion chamber is connected to the flue-gas passage by a transition opening, wherein the transition opening can be closed at least partially by a flue-gas flap. Both a primary air supply and a secondary air supply are provided. A first temperature sensor is arranged in the secondary exhaust-gas channel and controls the primary air volume flow as a function of the temperature in the secondary exhaust-gas channel, while the secondary air volume flow is held substantially constant.

Abstract: A burner comprising a fuel reservoir, a primary combustion zone located at the lower end of the fuel reservoir, a secondary combustion zone located underneath the primary combustion zone, a passage providing communication between the primary and secondary combustion zones, a flue for discharging products of combustion from the secondary combustion zone, the primary combustion zone having a peripheral wall incorporating air hole means to provide combustion air to the primary combustion zone, wherein the cross-sectional area of the air hole means is substantially equal to the combined minimum cross-sectional area of the passage and the minimum cross?sectional flow area of the flue.

Abstract: A wood or multi-fuel stove comprises a primary combustion chamber, a flue duct extending from an upper part of the primary combustion chamber; a grate defining a lower boundary for the primary combustion chamber, the grate extending from the front towards the back of the stove interior and having a front edge juxtaposed with the front of the stove; a secondary combustion chamber located beneath the grate linked to the primary combustion chamber; an inlet path for supplying fresh air to the secondary combustion chamber, the inlet path by-passing the primary combustion chamber; and an outlet path for conveying combustion products from the secondary combustion chamber to the flue, the outlet channel by-passing the primary chamber; the stove being characterized in that: the primary combustion chamber (X) is defined at least on its rear side by an insulated member (12); the grate (1) has: (i) a rear edge off set from the insulated member to leave a gap (G); extending over all, or part of, the width of the grate (1

Abstract: A heat exchanger for a multi oil furnace is disclosed wherein the external cabinet shell houses a central ventilation chamber divided into inlet and outlet sides by a generally vertical barrier. Combustion gases flow from the burner chamber into an upper bank of conduits and a lower bank of conduits, all of which pass horizontally through the ventilation chamber. Headers operably coupling the burner chamber, the upper and lower banks of conduits and a discharge opening define a flow path for the combustion gases created by the ignition of the used oil within the burner chamber. By positioning the burner chamber vertically between the upper and lower banks of conduits, the ambient ventilation air must pass over the burner chamber and the upper and lower banks of conduits twice while passing through the ventilation chamber, thereby providing a 360 degree loop of heat exchange.

Abstract: A multi oil furnace is disclosed wherein the front door is sealable against the burner chamber and against a lip extending around the circumference of a front header formed in the cabinet shell to operatively interconnect an upper bank of heat exchanger conduits with a lower bank of heat exchanger conduits. The exhaust gases flow from the burner chamber into the upper bank of conduits to the front header where the exhaust gases must flow around the burner chamber to the lower bank of heat exchanger conduits. The lip extending around the periphery of the front header is recessed below the lower bank of conduits to permit an accumulation of ash precipitated from the exhaust gases. The front door carries longitudinally offset sealing surfaces to seal against both the burner chamber and the header lip. Both the upper and lower banks of conduits, the burner chamber and the front header are accessible through the opening corresponding to the front door when moved to its opened position.

Abstract: A low profile gas burner fireplace is provided for mounting under a low table top or counter. The fireplace system comprises a decorative insulated table top mounted on the top wall of a low profile fireplace. The fireplace is provided with a hot exhaust gas system that connects below the burner system and passes through the bottom wall of the fireplace structure to conduct hot gasses through the bottom wall and outside of the room area in which the fireplace is located by means of an induced draft fan so that no pipes or exhaust system are visible in the room in which the fireplace is located.

Abstract: A solid fuel heating apparatus including a secondary combustion chamber in gaseous communication with a primary combustion chamber for increasing heating efficiency and for reducing polluting emissions. The secondary combustion chamber is lined with a refractory material. The entrance to the secondary combustion chamber is disposed at the bottom thereof adjacent the grate, and the grate containing the fuel is sloped at an acute angle with respect to the vertical to cause charcoal to accumulate adjacent to the orifice and to cover the entrance orifice of the secondary combustion chamber. Exhaust gases drawn into the secondary combustion chamber must first pass through the charcoal so that they are preheated prior to being mixed with secondary air. Means are provided for metering secondary air into the entrance orifice to cause mixing of the secondary air with the exhaust gases when the exhaust gases are at their maximum temperature.

Abstract: In order to eliminate flue gases generated in combustion of fuels in heating stoves a heating stove (1) is designed with a duct (14) above the fireplace (5) and closeable by means of a damper (16), whereby the flue gases pass through the bed of embers generated during combustion. A hearth (6) for the bed of embers is designed with obliquely set flat surfaces (26) for attaining of a concentrated bed of embers. There is located in the combustion chamber (58) of the heating stove (1) below the hearth (6) an aperture (9), which communicates with flue ducts (11), which communicate in turn with a flue (20), which discharges the flue gases from the heating stove. By means of a filling hatch (15) access can be gained to the interior of the said duct (14) to fill the heating stove and its fireplace with fuel.

Abstract: A high-efficiency clean burning heater for the burning of wood or coal is disclosed. The heater has a primary combustion chamber for the burning of solid fuel positioned above a secondary combustion chamber for the burning of combustible gases and pollutants which pass downwardly from the primary combustion chamber. Separate air supplies are provided for the two combustion chambers and the supply of air to the primary combustion chamber is governed by a damper plate to control the burn rate.

Abstract: Wood burning stove having several features for reducing emissions output and for improving energy efficiency by increasing the supply of oxygen to combustible materials, by increasing the mixing of oxygen with combustible materials, and by lengthening the residence time of combustible materials within the stove. The features include a turbulence-creating means positioned at an upper, front region of the combustion chamber, and a baffle located near the outlet for increasing both turbulence and the pathway of combustible materials exiting the stove.

Abstract: A stove for combusting both liquid and solid fuels, said stove comprising: a burner area in which the burner for liquid fuel is located, a collecting area for combustion gas above said burner area and connected therewith; a discharge conduit for the combustion gas connected to the horizontal upper wall of that collecting area; and a combustion area for solid fuel provided in said collecting area and extending itself over the full length of this area and consisting of a lower V-shaped plate, two vertically extending side plates and a horizontally extending upper plate, all these plates being positioned at some distance of the corresponding walls of said collecting area, openings being provided in the upper part of the side walls of said combustion area for allowing the combustion gas of the solid fuel to evade towards the discharge conduit.

Abstract: A stove comprises walls defining a main air inlet, a flue outlet and four chambers through which gas passes sequentially from the main air inlet to the flue outlet during normal operation of the stove. The chambers comprise a pre-heat plenum chamber into which the main air inlet opens, a main combustion chamber for containing solid fuel to be burned and into which gas passes from the pre-heat plenum chamber, a second combustion chamber which is downstream of the main combustion chamber with respect to the flow of gas from the main air inlet to the flue outlet, and a third combustion chamber from which the combustion gas outlet opens.

Abstract: A downdraft stove with a conical reaction chamber surrounded by a heat-insulating mass is disclosed. A tubular grating installed in the reaction chamber has a substantially vertically oriented central tube open at its upper end and connected at its lower end to an air inlet opening, and a cap supported above the open upper end, the space between the cap and the upper end constituting a primary air inlet nozzle. A plurality of grating tubes are radially distributed around and take off substantially horizontally from and communicate with the central tube, thereby defining a grating, and then turn downwardly into a conical shape conforming to the reaction chamber shape and are open at their downward ends to thereby constitute secondary air inlets. The downward-projecting ends of the grating tubes are twisted about the axis of the central tube in order to induce a swirling air flow pattern in the reaction chamber.

Abstract: A stove for burning combustible solid organic material, such as wood. The stove has a vertical fuel chamber with a combustion zone in the lower portion of the fuel chamber which is defined by an air inlet passage across the width of the fuel chamber and a convergent outflow passage at the bottom of the chamber. The combustion zone is shaped to provide a wedge-shaped area of incandescent coals during combustion in the combustion zone. No grate or other retention apparatus is needed in addition to the convergent outflow passage in order to retain fuel in place as it is consumed. The stove may be configured to provide radiant heat, as a forced air furnace, or as a boiler, or any combination of the three.

Abstract: A stove and method for burning solid fuels having an insulated primary combustion chamber, uniform distribution of preheated primary air through upward facing holes in a grate, downward flow of combustion gas through the grate, retention of hot coals in the grate structure, preheated secondary air, individually controlled primary and secondary air flows, insulated vortex combustion chambers for secondary combustion, longitudinally finned tubes as a first stage heat exchanger, plate-fin assembly as a second stage heat exchanger, an induced draft fan to draw the air and combustion gases through the combustion chambers as well as the heat exchangers, and a forced air fan to blow cool room air through the two stage heat exchanger.

Abstract: A downdraft furnace comprises a combustion component associated with a heat exchange component. The combustion component includes a fuel chamber, a primary combustion chamber and a secondary combustion chamber operatively interconnected by a constricting throat opening. Log support structure is provided to carry split logs and at an angle of approximately thirty degrees from the horizontal. The support structure and the logs define a primary air flow passage directed toward the throat opening through which primary air flow is directed at the bottom portions of the fuel segments. The inlet includes closure means to restrict and vertically vary slightly the path of primary air flow. Passage means are provided to introduce secondary air directly at the throat opening. The inlet includes closure means to restrict and vertically slightly vary the path of primary air flow.

Abstract: An improved heating apparatus, for example for use as a wood or coal burning parlor stove and providing a significant heat output, has a construction for reducing thermally induced mechanical stress and for enabling the interior baffle assembly components of the apparatus to be removed therefrom, for replacement if necessary, without dismantling the apparatus exterior frame. The elements of the interior baffle assembly are interconnecting and are secured in a mechanically stable configuration by single point connection to the apparatus frame. The apparatus can have primary and secondary combustion chambers and a baffle system for directing flue gases along a circuitous path from the secondary combustion chamber to an exit aperture whereby a significant proportion of the heat of said gases is given up to the apparatus. A vertically oriented downwardly directed two component baffle separates the combustion chambers.

Abstract: A heating apparatus for operating in one or the other of two combustion modes has a frame assembly enclosing a primary and secondary combustion chamber. A baffle, separating the chambers, provides for gaseous communication therebetween. Preheated primary and secondary combustion air is directed in a controlled fashion to the front of the frame assembly across a viewing window to keep the window clear. The apparatus further has an off center damper movement system, means for defining a secondary air flow path through the primary combustion chamber, and a structure which can be changed for operation either as a wood burning or a coal burning stove.

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 burning method and apparatus, using solid type fuel, comprising a combustion chamber in combination with a heat-extractor labyrinth chamber through which an artificial draft is generated mechanically. The artificial draft can be generated by intake and exhaust fans and/or blowers operating at accurately controlled speeds.In a specific stove-type embodiment, the draft-flow within the combustion chamber is utilized by a reversal of its flow pattern for either conventional up-draft burning, or preferably, for down-draft burning, with the gases exiting through the heat extractor compartment at close to ambient temperature and a short horizontal flue into the atmosphere. In this embodiment, the intake fan also serves to distribute usable heat from the surfaces of the combination and heat extractor compartments.

Abstract: A heating apparatus includes at least one combustion air inlet, a reverse-draft hearth having a grill positioned within a hearth plate, an ash receptacle for recovering combustion wastes, a fume outlet, a combustion chamber positioned under the reverse-draft hearth, and a heat recovery device. A heat transport and exchange fluid is adapted to be fed through the heat recovery device, and it circulates through the device in order to recover heat generated in the hearth. The heat recovery device also includes at least one casing positioned beneath the hearth, over the ash receptacle, and which is spaced from the walls of the heating apparatus. The rear portion of the casing is connected to the hearth plate so as to block combustion gases so that the combustion gases will pass over and thereafter under the casing prior to leaving the apparatus via the fume outlet.

Abstract: A sustained ignition secondary combustion apparatus in a housing of refractory insulating material includes a first level for conducting secondary air through a secondary air inlet and channel, and a second level for conducting smoke products. A partition separates the levels or zones. Openings are provided in the partition between the levels bounded by a high temperature porous or fiberlike material in the form of igniter tube elements. Secondary air and smoke products diffuse into the interstices of the porous or fiberlike material where contact and combustion maintains the igniter tubes at or above the ignition temperature. Ignition and secondary combustion of smoke products in the second level is therefore sustained and secondary air is preheated as it passes through the openings. A secondary combustion zone is defined in the region of the openings between the levels and continues down stream through the exhaust outlet.

Abstract: A wood burning stove having a lower main fire box and a vertically offset oven unit. Directly under the cooking surface of the lower firebox is an auxiliary firebox; the air supply inlet has means to selectively direct the incoming air to either firebox so that a small cooking fire can be used alone. The main firebox door has a glass panel and a removable stainless steel plate to reflect heat back to the glass to burn off accumulated deposits thereon.

Abstract: A heater which burns agricultural waste as its heat source includes a combustion chamber for the waste having a bottom opening, a grate for supporting the waste, an access lid at the top and an air intake at or adjacent the top. The bottom opening is connected to an exhaust system which includes a fan for creating a downward draft in the combustion chamber causing the exhaust gas stream to leave the chamber at the bottom opening. The exhaust system also includes elements for the removal of solid combustion products from the exhaust stream and for regulating the temperature of the exhaust stream which is then usable for heating purposes.

Abstract: A heating apparatus is disclosed wherein a combustion chamber which contains the fuel to be burned is located adjacent to an air heating chamber. Conduit means communicate from the air heating chamber to the combustion chamber for the purpose of leading air, which has been heated within the air heating chamber, into the combustion chamber. Blower means draw ambient air from the space surrounding the heater into the air heating chamber where it is blown through the conduit means into the combustion chamber to promote efficient combustion of the fuel.

Abstract: A space heater has a combustion chamber provided with hollow cheeks adapted for providing a supply of air into the combustion chamber at a level above the burner. The space heater incorporates a water boiler and a cooker unit which are arranged to be heated by combustion products in respective flues, each flue having a separate damper, whereby the flow of combustion products through each may be controlled individually.

Abstract: A downdraft woodburning stove in which there is improved combustion, heat transfer and combustion regulation comprising novel air inlet circulation, grate construction and automatic control of (1) temperature of exhaust gases and (2) of combustion air, and (3) the supplies of both primary and secondary air to a plurality of combustion areas.

Abstract: The disclosure is of a downdraft furnace fired by solid, carbonaceous fuels such as wood logs, coal and the like. The furnace is adapted for burning the fuel in three stages, to obtain complete combustion. The advantage of the furnace of the invention resides in its heating efficiency with few pollutants released into the atmosphere.

Abstract: This invention has to do with apparatus for burning solid fuels in successive stages whereby the fuel is completely converted to clean, hot, incombustible gases and to ashes, and, without admixture, transfers its heat to clean fresh air for distribution to areas to be heated.

Abstract: A heating stove for burning woodlike organic material having a fire box for receiving material to be burned substantially centrally therein. The walls of the fire box are sealed to render it substantially air-tight. At least one substantially vertically aligned draft tube depends downwardly from the cover of the fire box into the interior thereof for receiving combustion air at substantially atmospheric conditions from the upper end thereof and directing a flow to impinge upon the hearth adjacent the material to be burned from above and substantially in a vertical direction. Flue means are mounted on the fire box above the material to be burned and in spaced relationship with respect to the draft tube for removing the products of combustion and maintaining the fire box at a pressure below atmospheric pressure.