Abstract: A fireplace construction made of solid masonry units having a rear wall with a symmetrical bulge formed by a lower angled portion, a central vertical portion, an upper angled portion, and an upper vertical portion. Each portion is slightly spaced apart from the adjacent portion to provide a space for air to flow into the firebox. One or more air ducts route air from the room to the space between both the lower vertical portion and the lower angled portion and the space between the lower angled portion and the central vertical portion.

Abstract: A grill assembly is provided for selectively partially enclosing or exposing a grilling surface while providing a unique appearance. The assembly includes a base and a base pan coupled to the base. A cover is coupled to the base. The cover has a dome-shape extending over the base pan. The cover has a first section and a second section, each being pivotally coupled to the base. An opening extends laterally into the cover.

Abstract: A burner system for a fuel-burning fireplace having a fuel container with at least one aperture for combusting the fuel contained therein and an adjustable flame regulator for regulating a size of the flame. The flame regulator comprises a shutter for covering the aperture having a shape corresponding to the aperture, the shutter being variably adjustable between a first position (covered aperture) and a second position (exposed aperture); a handle extending from the burner system for variably adjusting the shutter; and a connecting member for connecting the shutter to the handle, the connecting member being secured to at least two extremities of the shutter; wherein movement of the handle allows a balanced movement of the shutter over the aperture.

Abstract: A fireplace is provided that includes a combustion space delimited by a combustion-space lining and accessible through a door or flap. The combustion-space lining is at least partially composed of a ceramic or glass-ceramic material. The fireplace also includes a wall element disposed on a side of the combustion-space lining that faces away from the combustion space so that so that an intermediate space is formed between the side and the wall element. A heat exchanger or insulating material can be positioned in the intermediate space.

Abstract: A fireplace system having a fireplace cavity and a secondary combustion assembly disposed adjacent to a rear wall of the fireplace cavity. The secondary combustion assembly includes a plurality of combustion chambers configured to facilitate secondary combustion. A plurality of inlets are disposed in the rear wall of the fireplace cavity. One or more of the plurality of inlets are configured to provide fluid communication between the fireplace cavity and a respective one of the plurality of combustion chambers. An exhaust gas collection chamber is in fluid communication with at least the secondary combustion assembly. The exhaust gas collection chamber includes a vent configured to release exhaust gas into a chimney. An ambient air bypass aperture is disposed in a top baffle of the fireplace cavity. The ambient air bypass aperture is configured to divert at least a portion of ambient air entering the fireplace cavity into the exhaust gas collection chamber.

Abstract: A fireplace including a combustion chamber enclosure with an opening and an inner pane positioned to at least partially cover the opening of the combustion chamber. An outer pane is spaced apart from the inner pane, the outer pane and the inner pane creating a space through which air moves, the air cooling the outer pane. A blower may be provided to move the air through the space. The outer pane may be angled with respect to the inner pane to enhance air movement.

Abstract: A fireplace for concurrent use inside and outside of a structure includes a combustion chamber enclosure defining a combustion chamber, an inside opening, and an outside opening, wherein the combustion chamber is viewable from the inside of the structure through the inside opening and from the outside of the structure through the outside opening. The fireplace also includes a combustion air plenum system coupled to the combustion chamber enclosure to supply fresh air from the outside to the combustion chamber and an exhaust opening defined by the combustion chamber enclosure for exhausting exhaust air from the combustion chamber to the outside of the structure.

Abstract: A wood burner includes a wrapper. A firebox is positioned in the wrapper that defines a combustion chamber. An air inlet is placed in communication with an external air supply. The air inlet includes a conduit to conduct the external air to the combustion chamber and a second conduit. A manifold is positioned above the firebox. The manifold is in communication with the second conduit, and includes one or more manifold chambers for permitting the external air received thereby to become heated. A plurality of air tubes connect to the manifold to receive the heated external air from the manifold, each plurality of air tubes including a plurality of apertures to direct the heated external air into the combustion chamber adjacent an upper inner surface of the firebox.

Abstract: An air filtration and sterilization system for removing airborne contaminants from air circulated through an air plenum system of a fireplace. Air filtration systems may include particulate, chemical, and ion filtration systems to filter the air. Air sterilization may include ultraviolet, ozone, germicidal coating, and channeled system of ducts systems to sterilize the air. Systems may be used individually or in combination. In addition, optional components, including a warning sensor for indicating when to replace a filter, an automatic initiation sensor for activating and stopping filtration and sterilization, and an air enhancement system for introducing desirable materials into the air, may be provided.

Abstract: A fireplace for concurrent use inside and outside of a structure includes a combustion chamber enclosure defining a combustion chamber, an inside opening, and an outside opening, wherein the combustion chamber is viewable from the inside of the structure through the inside opening and from the outside of the structure through the outside opening. The fireplace also includes a combustion air plenum system coupled to the combustion chamber enclosure to supply fresh air from the outside to the combustion chamber and an exhaust opening defined by the combustion chamber enclosure for exhausting exhaust air from the combustion chamber to the outside of the structure.

Abstract: A fireplace appliance for warming room air without line electrical connection has a high efficiency thermoelectric generator having a heat-rejecting surface connected to a heat sink. The generator has a heat-receiving surface facing the site where a fireplace flame is to be located. In one embodiment the generator provides power to operate a fan that forces air through an air duct. The air duct has an inlet port receiving a flow of room air, and an outlet port. The heat sink is placed in the air duct where airflow generated by the fan moves across and cools the heat sink. The air heated by the heat sink flows to the room through the outlet port. One suitable material for the thermoelectric generator is a Bi—Te semiconductor. A number of options are shown that allow fan operation to commence properly while the appliance begins a cold start.

Abstract: A combustion system for burning firewood including a combustion chamber defined by front, rear and side walls, a ceiling and a bottom. An access door is provided for addition of fuel into the combustion chamber. A substantial amount of combustion air enters the combustion chamber near the top of the fueling doors via apertures and is directed down the face of the fueling doors providing cooling. A geometry of the air metering orifice is either fixed or of limited adjustability such that the minimum flow of combustion air required for flaming combustion of a full load of fuel is maintained at all times. The combustion air flow cannot be reduced beyond a certain point and thus smoldering and very low air/fuel ratios are avoided.

Abstract: A combustion system for burning firewood including a combustion chamber defined by front, rear and side walls, a ceiling and a bottom. An access door is provided for addition of fuel into the combustion chamber. A substantial amount of combustion air enters the combustion chamber near the top of the fueling doors via apertures and is directed down the face of the fueling doors providing cooling. A geometry of the air metering orifice is either fixed or of limited adjustability such that the minimum flow of combustion air required for flaming combustion of a full load of fuel is maintained at all times. The combustion air flow cannot be reduced beyond a certain point and thus smoldering and very low air/fuel ratios are avoided.

Abstract: A novel dual mode of operation gas fireplace of the type having a combustion chamber box and a heat exchanger is provided with a burner in the bottom of the combustion chamber box which creates exhaust gasses to be passed out of the combustion chamber box and into or through the heat exchanger portion of the fireplace mounted on top of or back of the combustion chamber box. The hot exhaust gasses leaving the combustion chamber box may be directed into an exhaust stack or diverted directly into the room to be heated by a blower motor which diverts hot exhaust gas products from the heat exchanger directly into a room area to be heated in a ventless mode of operation. When the blower motor which diverts the exhaust gasses into the room is deactivated, the novel fireplace may be operated in a vented mode of operation.

Abstract: A gas fireplace insert structure having a firebox formed to direct flue gases reaching the upper section thereof through a folded path to flow forward and upwardly and then return rearwardly to an exhaust opening, and a casing formed to provide a room air circulating path around the firebox, the circulating room air path including a folded path portion disposed within and following the fold of the flue gas path.

Abstract: A gas fireplace insert for inserting into existing solid fuel fireplaces is made into modules that are separable for installation and can be later assembled together. A housing module which includes a combustion chamber supports a separable module comprising a duct for fresh air intake. The duct includes a connection collar for an air intake pipe leading to the interior of the duct. The duct also has a pass through collar for carrying exhaust gases from the fireplace. The collars can be attached to an exhaust pipe and air intake pipe respective, which extend through the existing chimney. The duct module is separated from the housing module for installation so that the pipe connections are easier to make with the lighter, smaller module.

Abstract: A novel wood/gas burning fireplace is provided with an open box shaped outer housing. A combustion chamber is mounted inside said housing having a plurality panels that are juxtaposed the panels of the outer housing so as to provide an open wall at the bottom, back and top of the fireplace which serve as a heat exchanger. An insulating panel is mounted in the top wall of the heat exchanger dividing the top wall into two separate passageways. The air passageway below the insulating panel comprises a part of a heat exchanger for heating room air of the space being heated. The air passageway above the insulating panel forms a plenum chamber with apertures in the outer housing panel(s) for conducting room air into the plenum chamber. A stack opening aperture in the top panel of the outer housing conducts cooling air into a coaxial exhaust stack for cooling the top panel as well as the exhaust stack pipe.

Abstract: A vent free gas fireplace comprises a housing and a firebox within the housing spaced-apart from the housing walls to provide top, bottom, rear and side plenums. The side plenums are divided into upper and lower side plenums. Room air enters the lower side plenum and passes into the rear plenum, the combustion chamber and the upper side plenum. Exhaust gases pass from the combustion chamber through a catalytic converter and into the top plenum. The hot exhaust gases are combined with room air from the rear plenum and pass into the upper side plenums, combining with additional room air, and then out into the room.

Abstract: An unvented gas-log fireplace is formed from a sheet metal member bent to form side and rear panels. A pair of spaced apart sheet metal plates are connected between the side panels and have rear edges spaced from the rear panel. The rear edges of the plates are bent to form lips extending in a direction toward the opposite plate. Bracket members are secured to the plates adjacent the side panels. A rear refractory member is positioned between the plates in engagement with the lips, and side refractory panels are positioned in abutment with a respective side sheet metal panel and held in place by the bracket members, the side ceramic panels abutting the rear ceramic panel at the sides thereof.

Abstract: A gas burning direct vent fireplace having an outer casing within which a firebox is mounted. The sides of the firebox are secured to the sides of the casing so that the bottom of the firebox is spaced above the floor of the casing without the need for supporting legs for the fireplace. An access door having a glass plate is fastened to the firebox at the front and a front panel is removably carried by the casing in front of and spaced from the glass plate access door, the front panel having an opening permitting viewing of the interior of the firebox through the glass plate. The mounting of the front panel permits a variety of selective front panels having varying aesthetics to be used with a fireplace.

Abstract: A draft hood is provided for mating alignment with a fireplace assembly. The mating alignment is facilitated by the location of alignment hardware fixed to the rear surface of the fireplace and to the inside of the draft hood. In use the hardware permits alignment of the draft hood in a fireplace enclosure without the need to see the fitting, without the need for a long run-in slide, and without the need vertically to pivot the draft hood on installation or to pull the flue termination forward of the firebox flue before attachment. For this purpose an updraft detection warning spill tube may also function as one of the alignment fittings since it is, due to its function, located near or at the junction of the draft hood and fireplace.

Abstract: A fireplace having a low density ceramic fiber duct with a first duct portion which promotes secondary combustion of unburned products of combustion and a second duct portion which removes products of combustion from the front of the combustion chamber. The ceramic fiber duct is positioned within the fireplace at a location along the flow path of the products of combustion that is intermediate the fireplace combustion chamber and flue. The first ceramic fiber duct portion includes a number of horizontally spaced and longitudinally extending circuitous, internal passageways which define the flow path as well as segregate the products of combustion. Due to their ceramic fiber construction, the passageways heat up quickly to promote secondary combustion of combustion products therein soon after fire ignition. In addition, the passageways are structured such that the combustion products must cover an extended exhaust path, which lengthens their stay within the heated passageways and promotes secondary combustion.

Abstract: The invention is directed to an induced draft fireplace including a plurality of outer walls defining an outer housing. The outer walls include at least one outer side wall and an outer top wall. A plurality of inner walls define a combustion chamber. The inner walls include at least one inner side wall and an inner top wall having an outlet opening. A room air circulation channel is defined by and disposed between the outer housing and the inner housing. The room air circulation channel has an inlet and an outlet. A heat exchanger is disposed in the room air circulation channel, and includes an inlet connected to and in fluid communication with the outlet opening, and an outlet. The heat exchanger includes a plurality of walls defining at least two flow paths extending in different directions, the at least two flow paths defining a total change in flow direction within the heat exchanger of at least 180.degree.. A fan having an inlet is connected to and in fluid communication with the heat exchanger outlet.

Abstract: A fuel-fired fireplace insert has a compact combination heat exchanger/draft hood structure extending interiorly along its top side and opening outwardly through an upwardly extending flue gas outlet and a dilution air inlet disposed on a top front side portion of the insert. During insert operation, hot combustion gas generated within its fire box portion flows upwardly into the interior of the heat exchanger/draft hood structure, is cooled by room air entering the dilution air inlet, and is discharged through the flue gas outlet. At the same time, room air enters the insert through an opening on a lower front side thereof, is heated by being passed externally along the fire box and the combination heat exchanger/draft hood structure, and is then discharged from the insert back into the room through openings adjacent the dilution air opening.

Abstract: A gas operated fireplace assembly is comprised of a plurality of modular components, including a casing, firebox, burner module and combustion air-intake module. The casing has an open front and is positionable in an enclosure adjacent a room with the open front facing the room. The firebox is insertable into the casing through the open front thereof and is removably mounted within the casing such that the firebox is removable therefrom without having to remove the casing from the enclosure. The casing can be installed separate from the other modules (e.g., during the "rough-in" phase of construction) and the other modules installed at a later time. Both the casing and firebox have respective top panels which are sloped at approximately 25.degree. to accommodate both a vertical and a horizontal flue configuration while maintaining the front-to-back depth of the fireplace assembly within acceptable limits.

Abstract: A fireplace including a heat exchanger beneath the combustion chamber floor. The front panel or surround of the fireplace housing includes a central opening which accesses the combustion chamber. Room air inlets and outlets, which are ducted to the heat exchanger, are horizontally arranged in a duct manifold that is positioned above the front panel opening. By positioning the room air inlets and outlets within the front panel opening rather than in the surround, the entire surround can be faced with marble, brick or other decorative material without having to provide a break therein for the ingress and egress of room air. A fan within the heat exchanger circulates room air in a flow path from the room being heated into the duct manifold inlets, through a first duct and into the heat exchanger, from the heat exchanger and through a second duct, and out through the duct manifold outlets. The fireplace also includes a raiseable hearth overlaying an opening accessing the heat exchanger fan.

Abstract: A fireplace, comprising an inner jacket and an outer jacket defining an air circulation path therebetween, is provided with a smoke chamber convection wall and a baffle convection wall oriented so as to efficiently transfer heat from the fire box to the air circulation path. A damper plate and a back draft blocking wall are positioned in the fireplace so as to effectively block back drafts in both the open and closed damper positions. The fireplace also includes exterior controls whereby the damper plate and an outside air vent can be controlled in a safe manner. A clean out shaft and a draft control are also provided to facilitate safe operation of the fireplace.

Abstract: The invention is directed to a balanced flue or direct vented, solid fuel burning fireplace which may be installed in a building and is operable at energy input levels greater than 75,000 BTU/hour. An enclosure including a top wall, bottom wall and four side walls defines a combustion chamber. At least one of the side walls includes an operable, sealed, transparent access door. A flue is connected to the enclosure and disposed in fluid communication with the combustion chamber and an outside ambient environment external to the building. A combustion air duct is connected to the enclosure and disposed in fluid communication with the combustion chamber and the outside ambient environment external to the building, whereby substantially all of the combustion air supplied to the combustion chamber flows through the combustion air duct when the access door is in a closed position.

Abstract: A fireplace insert for a fireplace cavity formed in a building with a fresh air inlet and a combustion gas outlet. The insert includes an enclosure dimensioned to be insertable within the fireplace cavity to define a combustion chamber for generating heat. A manifold is provided for distributing fresh air from the fresh air inlet to the combustion chamber. The manifold means is positionable at a predetermined location within the fireplace cavity according to the position of the fresh air inlet. A duct communicates the combustion chamber with the combustion gas outlet.

Abstract: A gas fireplace comprising a housing adapted to be located in a building. There is a first conduit in the housing to act as an air inlet. In insert is received within the housing. A second conduit in the insert aligns with and is received by the first conduit. The invention permits the construction of a gas fireplace in two stages, a first stage in which the housing is built into the building and a second, subsequent to all building activity, in which the insert is received within the housing.

Abstract: There is disclosed a refractory baffle for use in a fireplace which dispenses, via apertures provided therein, preheated combustion air over the central combustion zone of the fireplace. The refractory material substantially avoids warpage, flame quenching and other limitations associated with metal baffles.

Abstract: A fireplace has a manifold positioned between a combustion chamber and a flue. The manifold has a pair of inlets to supply dilution air to the flue, one extending from a front face of the fireplace, and the other from a rearward location. A baffle extends across the outlet of the manifold to prevent direct communication between the combustion chamber and flue. The inlet at the front face enables the flow of dilution air to be checked with the fireplace installed without having to accomodate the full flow of dilution air. The baffle prevents downdrafts from adversely affecting the combustion in the combustion chamber.

Abstract: A fireplace insert for a fireplace cavity that includes a venting passage comprising an enclosure dimensioned to be insertable within the fireplace cavity and fill substantially the entire cavity to define a combustion chamber. A passage and an aperture are provided for communicating the combustion chamber with the venting passage. There is a connection system for quickly and efficiently connecting the enclosure to the venting passage while the enclosure is within the fireplace cavity. The ability to connect the insert to the existing venting passage while in place permits the full fireplace cavity to be used. Previous inserts of this type were substantially smaller since there had to be room to manoeuvre and attach the vent by physically reaching into the fireplace cavity.

Abstract: A high efficiency clean burning fireplace for burning solid fuels at pyrolytic temperatures is provided with refractory walls maintained about 1100.degree. Fahrenheit at different burning rates. A top wall of the combustion chamber includes an exhaust stack and a primary air heat exchanger having an exhaust manifold for discharging primary preheated combustion air down and across the inside surface of glass panels in the doors of the fireplace. A secondary air heat exchanger is mounted below the primary air heat exchanger and separated therefrom by a top refractory panel in the combustion chamber. The secondary air heat exchanger exhaust manifold is in the combustion chamber and discharges secondary combustion air across the top of the combustion chamber and into the primary combustion air creating a high turbulence and complete burning of the secondary production of combustion while heating the refractory walls above a pyrolytic temperature at different burning rates.

Abstract: A gas log fireplace includes a firebox which defines a combustion chamber, a gas burner located within the firebox, an artificial log set, a log support member positioned on the gas burner, a heat exchanger connected to an exhaust gas outlet of the firebox and a convection chamber which surrounds the firebox and the heat exchanger for heating of room air. The gas burner is fabricated of a refractory fiber material. A combustible gas and primary air are mixed in a Venturi inlet tube of the gas burner. Highly aerated gas flows through front ports and top ports in the gas burner. Secondary air is directed to the front ports and the top ports to obtain highly efficient combustion and high heat output. The artificial log set, the support member and the gas burner define a partially enclosed cavity which is maintained at a high temperature during operation by reradiation from the artificial logs, the support member and the gas burner.

Abstract: An unvented fireplace heater assembly for directing heated air into an enclosure such as a room. The fireplace heater includes a combustion chamber mounted in spaced relation in enclosing panels. A plenum chamber is disposed in the panels adjacent to the unvented combustion chamber, and insulation may be selectively provided between the panels and the plenum chamber.

Abstract: A zero-clearance firebox with a much simplified construction enables efficient air exchange directly through one opening in which solid combustible materials are placed. The firebox has a metal inner shell and an outer shell of lighter gage metal incorporating a plurality of insulating materials in proximity with the outer and inner shells, including a ceramic blanket, rigid insulation, dead air space, and refractory brick. The firebox can be configured into a rectangle, a wedge or a semicircle for placement into a corner or along a wall of a room. The firebox can easily be adapted for use with liquid fuels such as natural gas, propane, etc. Finishing materials can be attached to the firebox to give the appearance of masonry or adobe.

Abstract: A fireplace and top wall assembly is disclosed. The top wall assembly includes primary and secondary aligned flue outlet assemblies that form between them a primary air conduit and a secondary flue gas conduit. Both of the conduits are designed to be mounted in fluid communication with the inlet opening of a chimney flue of a fireplace. Flue gases are drawn from the combustion chamber of the fireplace through the secondary flue gas conduit to mix air drawn in by the primary air conduit to promote cooling of the top wall assembly and surrounding fireplace structure.

Abstract: An improved wall shield and chimney support (WSCS) unit adapted to fit flush within the wall of a dwelling is disclosed. The WSCS unit includes ducts for ducting cooling air entirely around the inner wall of the unit and especially around the front lateral corners and top. The airflows are separated into outer and inner flows with the inner flow insulating the outer flow from combustion heat. The outer flow is then directed to the front of the unit top whereby a hot combustion unit can be brought into close juxtaposition with the WSCS unit without substantial danger of fire. Plural ducts are provided for cooling the rear wall of the unit, having inlets at the bottom rear of the fireplace unit, extending upwardly along the rear wall of the unit, and forwardly around the chimney, further cooling this area. The cooling of the chimney area is also increased by focusing the cooling air with baffles as it passes by the chimney.

Abstract: The invention relates to a heating device.A first object of the invention is to embody a heating device with a combustion space having at least one free side, such as an open hearth, or optionally a free-standing heater, such that it possesses a high yield. Another object is the embodying of this heating device such that in addition to use as a free-standing heater it can also be used as insert system for an open hearth. These objects are realized with a heating device characterized by a tilted, substantially U-shaped heat exchanger open to the front for heating air at the fireplace. This heat exchanger being provided with a lower heat exchanger part onto which can be laid solid fuel. For example, a number of pipes laid adjacent to one another, which lower part connects onto a standing heat exchanger part. For example, a number of pipes located at an interval from one another, such that the heat exchanger bounds the combustion space.

Abstract: The present invention relates to a gas-fired artificial log stove assembly, and more particularly to a gas stove assembly which visually simulates, in a realistic fashion, a traditional fire in a gas-fired stove stacked with horizontally disposed artificial logs, and which at the same time supplies substantial space heat to the surrounding room environment by heating room air circulated through a heat exchange mechanism.

Abstract: In a fireplace unit having an open sided firebox formed by opposed side walls, a top wall, a bottom wall, a rear wall, and a connection in the top wall to an exhaust flue, the present improvement including an intermediate wall member of overall curved configuration mounted in the firebox opening, the intermediate wall member being spaced from the rear wall of the firebox and extending between the opposed side walls and, at least, the bottom wall thereof to define a substantially enclosed space in the firebox opening therebehind, the curved configuration of the intermediate wall member increasing the reflective and radiant characteristics of the interior of the firebox thereby improving its overall efficiency and heat transfer capabilities. The various embodiments of the intermediate wall member disclosed herein may be attached to the firebox by fasteners, by welding, or by other suitable arrangements, or such intermediate wall member may be integrally formed as part of the firebox itself.

Abstract: The unit restores existing, masonry fireplaces without entailing dismantling of the latter. A heating jacket base, heating jacket, smoke chamber and flue lining are set into the existing firebox, smoke chamber and flue. Ducting is provided to move heating air through the heating jacket, and ducting is provided to pass combustion gases into the smoke chamber and flue. Internal air, or outside air, is accommodated in the unit for heating and combustion. Blowers are provided to move the heating air into the fireplace site (room) and/or to draw in outside air simply to exchange interior, stale air.

Abstract: An improved fireplace unit adapted to fit flush within the wall of a dwelling is disclosed. The fireplace unit comprises duct means for ducting cooling air entirely around the inner wall of the unit and especially around the front lateral edges and top, whereby flammable building materials can be brought into close juxtaposition with the unit without substantial danger of fire. Plural ducts are provided for cooling the rear wall of the unit, having inlets at the bottom rear of the fireplace unit, extending upwardly along the rear wall of the unit, and forwardly around the chimney, further cooling this area. The top wall of the unit comprises an integral support member and thermal break which allows the unit to support a conventional chimney without further support structure and provides a substantial thermal break between the chimney and the front wall of the unit.

Abstract: The fireplace has a coaxial vent directly venting the exhaust gas through its top. The fresh air is directed through an outer jacket of the coaxial vent to a chamber located between the firebox and the rear panel and enters into the lower portion of the firebox while the exhaust air is conducted through the inner coaxial duct, located inside the fresh air duct, to be released to the outdoor. Residual heat in the exhaust gas is inherently recycled by the fresh air being drawn into the fireplace to enhance combustion and to increase the efficiency for heating purposes.

Abstract: The assembly is adapted for installation as a free standing unit, a fireplace insert or a whole masonry fireplace. It comprises a primary combustion chamber, similar to a traditional fireplace, with the back wall of the primary combustion chamber being a common wall shared with a second combustion chamber. The secondary combustion chamber is vertical and discharges directly into the hood. The primary combustion chamber is vertical from the grates to the hood, where the flue gasses are forced to travel horizontally the depth of the grates and then enter the hood. The gasses from the primary chamber then mix with the heated gasses from the secondary chamber and reignite to initiate tertiary combustion. An angled grate is used and the grate is even with the intake of the secondary combustion chamber, which causes a horizontal draft to occur over the fire. An air duct, originating out of doors, is attached to the base of the assembly. The entire base of the fireplace is an outside air manifold.

Abstract: A stove with a continuously open draft provides a fire chamber peripherally configured to cause circular motion of burning gases therein to provide substantially complete combustion of fuel. A continuously open elongate draft vent is positioned above and immediately inwardly of a door window to aid cleaning of that structure and to reinforce the circular motion of combustion gases. Baffles and exhaust dampers also are configured to aid the circular motion of combustion gases in the fire chamber. Heated surfaces defining the upper fire chamber walls catalyze the combustion reaction and rearward surfaces reflect radiant energy back into the combusting fuel to further aid combustion.

Abstract: A zero clearance fireplace of the type to be installed inside of a building against or near an outside wall is provided. The box shaped fireplace is provided with four substantially vertical walls, a top wall and a bottom wall. The bottom wall comprises an inner plenum and an outer plenum below the combustion chamber. The rear wall comprises an outer plenum connected to the bottom plenum of the bottom wall, a middle plenum connected to a source of fresh air and connected to the inner plenum of the bottom wall and an inner plenum which is connected to a horizontal exhaust pipe which is inserted through the outside wall and is connected to the combustion chamber through a baffle arrangement.

Abstract: A double walled fireplace insert is shown with an inner firebox and an outer shell to provide convection air channels between the parallel walls of the inner and outer units. A front panel is integral with the outer shell, and it covers the front of the insert. This front panel has room air intake vents that open into the said air channels, and warmed air outlet vents that open into the room to be heated by this fireplace. There is a circulating fan positioned within the convection air channels for governing the air movement through the said channels.