Abstract: The invention relates to a solid-fuel heating apparatus that includes a combustion chamber (1) and a first flue-gas discharge duct (6), characterized in that the heating apparatus includes: a dual wall (2A) defining a second flue-gas discharge duct (2) located outside the combustion chamber and on the flue gas path between the combustion chamber (1) and said first duct (6), and provided in a vertical section thereof with a plurality of controlled communication valves (11, 12, 13, 14, etc.) arranged at respectively different heights (h1, h2, h3, h4, etc.), the second flue-gas discharge duct (2) being adapted via an opening (2B) in the lower portion of the dual wall (2A) so as to extend the flow path of the flue gas by an amount depending on the selection of the open inlet valve in the second duct (2) while the others are closed; adjusting means adapted for selecting, for each of the valves (11, 12, 13, 14, etc.

Abstract: This invention relates to a method and apparatus for the extraction of heat and smoke from a fuel burn in a firebox. The design is for the firebox exhaust area to be wrapped with its own hot exhaust gases, for smoke extraction, and then, for heat extraction, have all of the outer surface of a stove, fireplace or furnace exposed to said hot exhaust gases. Such a wrap-aroung design burns smoke from said exhaust gases, holds a high temperature in the firebox area, for good combustion, and increases the efficiency of heat extraction by using all of the outer surface of the stove, fireplace or furnace as a high temperature heat exchanger.

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: The invention relates to a combustion method and apparatus for carrying out this method.The method comprises establishing (a) a combustion zone of hot embers above and near a grate and (b) a column of particulate fuel above and resting on said hot embers, supplying combustion air to said combustion zone only, flowing products of combustion generated at the interface between said hot embers and particulate fuel and in said hot embers downwardly through said grate, then upwardly in heat exchange relation to air in a space to be heated, and finally to exhaust.The apparatus comprises means for holding a column of particulate fuel above a grate, means for flowing air into a combustion zone above and adjacent to said grate at the bottom of said column only, and means for flowing products of combustion downwardly through said grate then upwardly through a heat exchange zone to exhaust.

Abstract: A stove for heating a room has three coaxially nested tubular columns formed of superposed rings of ceramic material, these columns defining an innermost channel rising above a combustion chamber to carry off evolving flue gases, an intermediate channel in which the flue gases descend, and an outermost channel which is subdivided by a cylindrical metallic partition into an inner and an outer cylinder section, the former serving as a duct for the escape of the flue gases to an elevated exhaust while the latter is traversed by air to be heated through that partition. Passages connecting the combustion chamber with the inner channel section help entrain an initial gas flow, during start-up, through the descending path of the intermediate channel.

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 solid fuel-burning stove has a fire chamber defined by its walls and top and an upper gas recirculating chamber with a convex portion is provided in the top section of the stove.

Abstract: An efficient space heating stove having a combustion chamber substantially completely enclosed with insulating firebrick whereby the operating temperatures within the combustion chamber can be maintained above the ignition temperature of the fuel being consumed. Combustible gases liberated by the wood fuel are burned as they pass through a perforated, hollow, tubular member located within the combustion chamber and through which the combustible gases must pass before they are exhausted from the stove. Fuel within the combustion chamber is efficiently burned before useful heat energy is extracted.

Abstract: This stove invention relates to wood and coal burning stoves employed for heating. More effective draft control and heat transfer is achieved by a stove (11) employing straight and serpentine flues (46, 48), a control rod (43) to coordinate movement of a baffle (38) and damper (41) for defining passageways to the flues, and a channel (33) for apportioning air above and below the fuel and into first and second combustion chambers (26, 27).

Abstract: A stove or furnace in which the products of combustion are recirculated inside the combustion chamber by means of a V-shaped partition or baffle, the apex of which extends downward directly above the primary fire zone, so that the combustion products rising from the fire are deflected outward and then flow downward back into the primary fire zone. Secondary air may be mixed with the unburned combustion products above the primary fire zone to form a combustible mixture which is burned on re-entering the fire zone.

Abstract: Fireplace furnace apparatus includes separate air systems for combustion and for heating and the combustion gases flow from a primary combustion chamber into a secondary combustion chamber and into additional settling chambers for particulate matter and the heated air flows through finned chambers adjacent the chambers through which the combustion air flows.

Abstract: An inner shell is incorporated within an outer shell and is of smaller dimensions to provide side spaces for the upward flow of heat, a top space communicating with an outlet, and a rear space having a V-shaped baffle therein causing upward flow of heat in the rearward area to be circulated and slowed for increased heating efficiency. An extension is attachable to the baffle for extending it upwardly and forwardly to control the flow of heat at the baffle. The inner shell has an imperforate tray extending from side to side and arranged to be moved forwardly through an opening in the inner shell and providing a natural forced flow of heat around it from the bottom for heating room areas.