Abstract: Heating a room in a structure with a fireplace includes feeding combustible gas to a burner of a combustion assembly of the fireplace to create heat and flames with hot exhaust air passing out of a combustion chamber of the fireplace through an exhaust duct and into an exhaust air conduit of a secondary heat exchanger and out of the structure.

Abstract: The present disclosure provides woodstoves that, optionally, produce low emissions. In certain embodiments, the woodstove includes a housing, a firebox disposed in the housing, an air regulator and a secondary air pipe. The air regulator includes a primary air aperture configured to supply primary air to a fire located in the firebox, a plurality of secondary air apertures configured to supply secondary air to a combustible gas emitted by the fire, and a secondary air damper. The present disclosure also provides methods of operating such a woodstove. As measured according to Method 28 of the U.S. Environmental Protection Agency, the weighted average emission rate of the woodstove of certain embodiments of the invention is no greater than about 4.5 grams of particulate emissions per hour.

Abstract: A domestic apparatus, such as a cooking appliance, uses hydrogen and, optionally electrical heating, to cook food. The cooking appliance may have a cooking surface (e.g. a grilling surface) so as to result in an indoor barbeque, which may be used with no venting or reduced venting requirements.

Abstract: A combustion air and exhaust gas balancing system for use with a direct-vent heater appliance. The balancing system includes a combustion air valve in fluid communication with a combustion air duct and an exhaust gas valve in fluid communication with an exhaust gas duct. The combustion air valve is operatively coupled to the exhaust gas valve with an actuator. The combustion air and exhaust gas valves are shaped and sized so that a single operation of the actuator simultaneously adjusts the flow of combustion air into the firebox and the flow of exhaust gas out of the firebox and provide selected flame characteristics in the firebox. In one aspect of this embodiment, a movement of the actuator in a first direction simultaneously increases the flow of combustion air and exhaust gas, and a movement of the actuator shaft in a second direction simultaneously restricts the flow of combustion air and exhaust gas.

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: A fireplace assembly comprises a smoke chamber and a firebox in fluid communication with the smoke chamber. A masonry casing partially surrounds the firebox, the casing having a pair of spaced-apart side walls which together define an opening to the firebox. In one aspect of the invention, a lintel supports at least one chimney breast block across the opening, the lintel extending between the side walls and being supported by the side walls. In another aspect of the invention, a damper is mounted above the smoke chamber. In another aspect of the invention, the firebox is comprised of a plurality of firebrick, a metal firebox frame for guiding installation of the firebrick, and insulation between the firebox frame and the firebrick. In yet another aspect of the invention, insulation surrounds the back and sidewalls of the firebox and smoke chamber.

Abstract: A balanced building ventilation system that employs a fireplace as an element of the ventilation system. The fireplace includes a firebox, and an exhaust gas flue is connected to the firebox for exhausting gas from the firebox to the outdoor ambient. A ventilation channel conveys outdoor ambient air into the building interior. A motor-driven draft inducer is connected to the exhaust gas flue for forcing exhaust gas flow out to the outdoor ambient. A motor-driven blower is provided for forcing ventilation airflow through the channel to replace building interior air lost to exhaust gas flow.

Abstract: A fireplace assembly comprises a smoke chamber and a firebox in fluid communication with the smoke chamber. A masonry casing partially surrounds the firebox, the casing having a pair of spaced-apart side walls which together define an opening to the firebox. In one aspect of the invention, a lintel supports at least one chimney breast block across the opening, the lintel extending between the side walls and being supported by the side walls. In another aspect of the invention, a damper is mounted above the smoke chamber. In another aspect of the invention, the firebox is comprised of a plurality of firebrick, a metal firebox frame for guiding installation of the firebrick, and insulation between the firebox frame and the firebrick. In yet another aspect of the invention, insulation surrounds the back and sidewalls of the firebox and smoke chamber.

Abstract: A fireplace adapted for attachment to a flue pipe assembly including an exhaust pipe and a surrounding fresh air pipe is provided. The fireplace comprises an interior housing. The interior housing forms a combustion chamber. The fireplace also comprises a top wall, a rear wall and side walls. These walls define an exterior housing about the combustion chamber. A combustion air flowpath is defined within the housing through which air for combustion is brought from outside the housing into the combustion chamber. The fireplace also comprises a top port formed in the top wall and a rear port formed in the rear wall. Each of the top and rear ports include a first portion that communicates with the combustion chamber and a second portion that communicates with the combustion air flowpath. Finally, the fireplace comprises a vent pipe assembly. The vent pipe assembly includes an inlet air pipe member and an outlet air pipe member. The outlet air pipe member is connectable with the selected port at the first portion.

Abstract: A fireplace assembly comprises a smoke chamber and a firebox in fluid communication with the smoke chamber. A masonry casing partially surrounds the firebox, the casing having a pair of spaced-apart side walls which together define an opening to the firebox. In one aspect of the invention, a lintel supports at least one chimney breast block across the opening, the lintel extending between the side walls and being supported by the side walls. In another aspect of the invention, a damper is mounted above the smoke chamber. In another aspect of the invention, the firebox is comprised of a plurality of firebrick, a metal firebox frame for guiding installation of the firebrick, and insulation between the firebox frame and the firebrick. In yet another aspect of the invention, insulation surrounds the back and sidewalls of the firebox and smoke chamber.

Abstract: A direct vent gas fireplace has a combustion air supply duct extending down the back wall, on the outside of the housing back wall. It is connected to the firebox by a duct assembly with a flange that connects to the housing and two ducts that connect to the firebox. The supply duct is located laterally between two cooling air ducts that lead from the cool air zones at the bottom outer corners of the housing to a cooling air plenum inside the top of the housing. Inside the cooling air plenum and the cooling air ducts are a room air plenum and room air circulating space for the circulation of room air to be heated. This provides a compact construction with adequate wall cooling without the need for additional thermal insulation.

Abstract: For use with a fireplace, a heat exchanger mounted across the top portion of the fireplace with the heat exchanger comprising a heat exchanger core with four identical extruded core sections connected together around an inner spin chamber for the passage of combustion gases and surrounded by an outer spin chamber for the passage of combustion gases, with each core section having a center core passageway for the passage of room air and the heating of the room air by the heat from the combustion gases being transferred to the room air through the heat exchanger cores, and tortuous passageways between the core sections from the outer spin chamber to the inner spin chamber to increase the area of contact by the hot combustion gases to the core sections and to increase the dwell time of the combustion gases in the core to increase the amount of heat transferred to the combustion gases to the room air in the core sections.

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 fireplace has a firebox with a controllable outside air vent to provide a source of cooler air for mixing with and modulating the temperature of the air heated by the fireplace. The air vent is vertically formed between a combustion chamber and a surrounding shell so that a convective current causes the air to flow therethrough and pass over the top surface of the combustion chamber to keep it cooler than otherwise possible with heated room air. Convective currents in another air duct formed between the shell and the combustion chamber circulates room air around the combustion chamber to transfer heat to the room air. The warmed outside air and room air mixes in a plenum above the fireplace prior to entering the room, thereby modulating the temperature of the heated air and permitting it to burn without excessively heating the room. A damper regulates the flow of outside air into the air vent, as desired.

Abstract: The invention relates to a direct vent gas fireplace adapted for attachment to a concentric flue pipe assembly having an exhaust pipe and fresh air pipe. A top wall, rear wall, bottom wall and side walls define a combustion chamber. A gas burner is disposed in the combustion chamber. A slanted flue attachment wall is attached to and extends between the top wall and rear wall. The slanted flue attachment wall is disposed at obtuse angles relative to the top wall and rear wall. A first pipe member is orthogonally attached to the flue attachment wall and is in fluid communication with the combustion chamber for conveying combustion products from the combustion chamber. A second pipe member having a diameter larger than the first pipe member is disposed concentrically around the first pipe member. The first and second pipe members define an annular space therebetween forming an air intake duct.

Abstract: A process and apparatus for combustion of a gaseous fuel in a fireplace in which a plurality of periodic vortices are created in the airflow pattern of the combustion air prior to its mixing with the gaseous fuel, thereby producing a more natural looking, flickering flame.

Abstract: A system for heating the air in the room containing a fireplace includes a heat exchanger mounted at the top portion of the combustion chamber of the fireplace to extend across the chimney flue opening and a fan for circulating room air through the heat exchanger in heat exchange relationship with the combustion gases passing from the combustion chamber in a vortex flow through a heat exchange passage in the heat exchanger to the chimney flue opening. There are preferably provided a pair of the heat exchangers mounted in side-by-side relationship to conform with the rectangular shape of the plan view of the fireplace.

Abstract: A combustion air kit for providing a source of external air to feed a fire in a firebox is installed during new construction or as a retrofit unit into existing fireplaces. A masonry air vent brick having a hole therein air flow is included in the combustion air kit. The flow of air through the brick and to the firebox is regulated by a spinner cap mounted for rotation on a threaded post seated within a plug contained in the air vent brick. The air vent brick is connected to a flexible duct which is attached at an opposite end to a vent inlet brick located on the external of the house, chimney or other structure. The vent inlet also includes a vent inlet cover to provide an attractive inlet for the air to the firebox.

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 novel dual direct vented fireplace includes a combustion chamber having two permanent exhaust outlets including a horizontal exhaust outlet and a vertical exhaust outlet. A fireplace enclosure surrounds at least the top, bottom and back of said combustion chamber forming three hollow plenum walls around the combustion chamber. A fresh air duct in the top and back plenum walls connects to a combustion air passageway under the gas burner system. Two permanent air inlets in said fresh air duct include a horizontal air inlet and a vertical air inlet. A coaxial pipe is provided for connection to at least one of said exhaust outlets and one of said air inlets. The other of said exhaust outlets and air inlets is covered with a closure whereby the dual direct-vented fireplace is assembled at the factory or in the field as either a horizontal or a vertical direct vented fireplace.

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: A method and adaptor assembly are provided for installing a direct vent firebox, such as a gas fireplace insert, into an existing fireplace. An exhaust flue liner and inlet flue liner are installed in the chimney of the existing fireplace. A plate flue collar is aligned above a fastener plate flue collar. The lower ends of the exhaust flue liner and inlet flue liner are connected to the fastener plate flue collar above an exhaust opening and inlet opening formed in the fastener slider plate, respectively.

Abstract: A system for heating the air in the room containing a fireplace includes a heat exchanger mounted at the top portion of the combustion chamber of the fireplace to extend across the chimney flue opening and a fan for circulating room air through the heat exchanger in heat exchange relationship with the combustion gases passing from the combustion chamber in a vortex flow through a heat exchange passage in the heat exchanger to the chimney flue opening. There are preferably provided a pair of the heat exchangers mounted in side-by-side relationship to conform with the rectangular shape of the plain view of the fireplace.

Abstract: The space heating system has a stove (1, 2) with a sealed combustion chamber (3); air is heated in the stove in a heat exchanger (12) therein, and heated air is conducted through hollow blocks (80) of chamotte arranged, for example, as heating panels, heated walls, benches, floors or the like. The hollow blocks are formed, internally, with projections or obstructions (83) to increase heat transfer, and may be faced at the outside with decorative tiles. To seal the combustion chamber, a vertically movable panel, typically of fire-resistant glass, is slidably located in front of a fuel inlet opening (7). In operation, the panel is sealed, so that the combustion chamber (3) will receive air only under controlled conditions, in two air paths; a primary air path supplies air to a narrow space (22) below a fuel support grate (25), after being preheated by passing around an ash receiver (18); and a secondary air flow, passed through ducts (30) within the combustion chamber, and ejecting air towards the panel.

Abstract: A fireplace assembly of the type used as a room air heater comprises a second pane of glass in front of and spaced from the glass pane forming the front of the combustion chamber. The two panes form an air passageway for delivering intake air from an upper vent to the bottom of the combustion chamber. The intake air cools the panes of glass such that a relatively inexpensive glass material can be used and such that the front of the fireplace assembly is relatively cool to the touch.

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: The invention relates to a direct vent gas fireplace adapted for attachment to a concentric flue pipe assembly having an exhaust pipe and fresh air pipe. A top wall, rear wall, bottom wall and side walls define a combustion chamber. A gas burner is disposed in the combustion chamber. A slanted flue attachment wall is attached to and extends between the top wall and rear wall. The slanted flue attachment wall is disposed at obtuse angles relative to the top wall and rear wall. A first pipe member is orthogonally attached to the flue attachment wall and is in fluid communication with the combustion chamber for conveying combustion products from the combustion chamber. A second pipe member having a diameter larger than the first pipe member is disposed concentrically around the first pipe member. The first and second pipe members define an annular space therebetween forming an air intake duct.

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 direct ventilation gas fireplace having co-linear air intake pipe and gas outlet pipe. The pipes are separated from each other so that the fluid flowing in one pipe does not come in contact with the other pipe. The gas outlet pipe may comprise a safety release valve that allows any excess pressure, in case of explosion, to exit through a lateral spring-actuated door into an enclosure closed around the combustion chamber. This safety release valve allows to build fireplaces having pipes longer than the usual length allowed for respecting specific safety tests in case of gas explosion.

Abstract: A fireplace comprises a firebox which has a flue and front, bottom, top, rear and side panels. An outer casing is spaced from and surrounds the firebox. A combustion air plenum is positioned at a point above the bottom of the firebox and is connected to a conduit that communicates with a source external to the room in which the fireplace is situated for supplying combustion air to the fireplace. The firebox has a combustion air entry port in at least one of side panels of the firebox near the bottom of the firebox for supplying combustion air to the interior of the firebox. The combustion air port communicates with the combustion air plenum through a first passage. The flue passes upwardly through the firebox and is adapted to be connected to a second conduit that is in communication with a source external to the room which the fireplace is situated for exhausting the combustion gasses from the fireplace.

Abstract: An air guide element is installed between air supply vent and the inside of he door of the heating appliance which consists of an adjustable damper for regulating the supply of secondary combustion air and ballast air in the appliance and in which at least one heat sensitive element is connected between said damper and one of the components of the heating appliance which serves to adjust said damper, which element reacts to the prevailing temperature in the combustion chamber of the appliance.

Abstract: A direct vent gas fireplace has a firebox surrounded by an enclosure. The enclosure has an inclined surface between the top, rear and sides. The surface is inclined at approximately 45 degrees and has an exhaust opening. The firebox has an inclined surface parallel to the inclined panel and has an aperture in each side of the firebox. A duct connects each of the apertures to the exhaust opening. A heat exchanger lies between the inclined surfaces in line with the duct. The surface has a gap in it which connects through an air combustion conduit to the bottom of the firebox. The conduit may be pre-formed. An angle adaptor has an inner cap over the exhaust opening and an outer cap over the inner cap and the gap. The adaptor may be mounted vertically or horizontally. Alternatively, an inclined plate may be placed over the inclined surface with a hole concentric with the opening and of greater area. A first wall of a double walled vent duct may enclose the opening, while the second wall encloses the hole.

Abstract: An insertable gas conversion unit for insertion into existing wood burning fireplaces comprises an insertable gas fireplace conversion unit having a fire box combustion chamber and a gas burner mounted therein. The combustion chamber is covered with a decorative glass door. The conversion unit comprises a first coupling unit which is connected to the chimney of the exhaust outlet of the existing fireplace and further comprises a second coupling unit which is connected to the exhaust gas outlet of said fire box of said conversion unit. Said first and second coupling units telescopically fit one into the other during the assembly and insertion of the gas fireplace unit in the existing wood burning fireplace so as to provide a gas fireplace conversion of a wood burning fireplace without requiring any custom fitting or parts.

Abstract: A zero clearance fireplace of the type adapted to be installed against an outside wall of an interior space or room to be heated is provided with six walls which comprise four substantially vertical walls, a top wall and a bottom wall at least two of said vertical walls having airtight glass side walls connected to the frame structure of the fireplace. The bottom wall, the vertical side wall and the top wall are provided with plenum structures which are inner connected to form a heat exchanger. The rear wall is provided with a vertical inner plenum in which outside fresh air is introduced and conducted into a bottom inner plenum below the combustion chamber of the fireplace to provide fresh outside air to the gas burner system in the combustion chamber.

Abstract: It comprises a hollow base (1) which is connected on the one hand to an evacuation conduit (9), on the other hand to smoke collector tubes (8) which open out upwardly at the apex of a liftable cover (2) with transparent walls. Between this cover (2) and the base (1) there is interposed an admission duct (3) which is pierced with upper slots (3a) and with at least one lateral opening (3b).

Abstract: The air supply system for feeding air to a firebox within a building comprises a fresh air intake box (3) in the outside building wall (19) and, in the immediate vicinity of the firebox, a distributor box (7), connected with several pipes (5a, 5b, 5c, 5d). The fresh air intake box (3) has an extensible tube (25) for adaptation to varying wall thicknesses of the outside building wall (19). The prefabricated parts can be readily installed on the building site. By the use of several pipes (5a, 5b, 5c, 5d), the individual pipe cross section can be kept at a small value so that no static impairment of the building ceiling (11), wherein the pipes (5a, 5b, 5c, 5d) are extended, occurs. Advantageously, a fan can be installed in the extensible and readily removable tube (25) in order to increase the flow velocity of the fresh air; servicing of the fan is possible without any problems.

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 zero clearance fireplace of the type adapted to be installed against an outside wall of an interior space or room to be heated is provided with six walls which comprise four substantially vertical walls, a top wall and a bottom wall at least two of said vertical walls having airtight glass side walls connected to the frame structure of the fireplace. The bottom wall, the vertical side wall and the top wall are provided with plenum structures which are inner connected to form a heat exchanger. The rear wall is provided with a vertical inner plenum in which outside fresh air is introduced and conducted into a bottom inner plenum below the combustion chamber of the fireplace to provide fresh outside air to the gas burner system in the combustion chamber.

Abstract: A fireplace combustion system in which a sealed firebox contains: a base having apertures connected to a source of combustion air and wherein a hollow grate is connected to one of the apertures to conduct combustion air to a quantity of fuel disposed on the grate; a plurality of baffles and deflectors are utilized to direct the products of combustion above the grate for flow through a quantity of porous refractory material so that the refractory material is heated by the products of combustion to a temperature sufficient to ignite the unburned gases present; and a flue for exhausting the products of combustion. The grate is provided with a plurality of apertures at various levels above the bottom to supply combustion air at varying temperatures at different locations in the burning fuel. Suitable valve means are used to control the amount and direction of the air flow through the apertures in the base to different primary and secondary burning zones in the firebox.

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: 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: An outside air supply control apparatus for a fireplace comprising a first cylindrical pipe for connection to an outside air supply, the pipe containing at least one aperture in its wall. A second cylindrical pipe having an inside diameter slightly larger than the outside diameter of the first pipe, and having a closed end, is disposed coaxially over the end of the first pipe. The second pipe has an aperture in its wall which can overlap the aperture in the wall of the first pipe when rotated to a first position, and has an unapertured portion which can completely block the aperture in the wall of the first pipe when rotated to a second position.

Abstract: A fresh air vent for building into the hearth of a fireplace is constructed with the shape and heft of a hearth brick. It has a body and lid of heavy-gauge steel, the body replacing a hearth brick in the hearth, and defining a screened top opening to a tubular flange extending most of the depth of the vent so as to establish a secure connection to an air duct without the use of tools. The lid is hinged to the back of the body, and has slightly inclined end walls passing through and retained in slots in the top of the body to establish frictional engagement therewith when the lid is open.