Abstract: Heating devices and methods for mitigating heating device pollution are generally described. In an example embodiment, a heating device includes a primary combustion chamber for combustion of a fuel. A first and a second secondary combustion chamber are in fluid communication with the primary combustion chamber for receiving an exhaust flow of combustion products from the primary combustion chamber and are configured for combustion of one or more combustion products received from the primary combustion chamber. The first and second secondary combustion chambers may provide parallel fluid paths from the primary combustion chamber. A secondary combustion selector is provided for selectively allowing the exhaust flow through the first and second secondary combustion chambers.

Abstract: Heating devices and methods for mitigating heating device pollution are generally described. In an example embodiment, a heating device includes a primary combustion chamber for combustion of a fuel. A first and a second secondary combustion chamber are in fluid communication with the primary combustion chamber for receiving an exhaust flow of combustion products from the primary combustion chamber and are configured for combustion of one or more combustion products received from the primary combustion chamber. The first and second secondary combustion chambers may provide parallel fluid paths from the primary combustion chamber. A secondary combustion selector is provided for selectively allowing the exhaust flow through the first and second secondary combustion chambers.

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 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 solid fuel burning stove includes a firebox having front side and rear walls, a top and a bottom, and a secondary combustion unit formed from high temperature insulative refractive material mounted on the top and rear wall of the firebox. The unit is connected to the firebox by a mouth located in the rear wall adjacent the floor of the firebox and by a perforated plate on the firebox top wall. A vertical combustion passage extends from the mouth up to a mixing and combustion chamber located in the unit above the top wall of the firebox. The secondary combustion unit efficiently burns secondary combustion gases flowing into the unit through the mouth and plate during different stages of burning solid fuel, particularly wood.

Abstract: A pellet burning stove includes a firebox defining a combustion chamber, a pellet burner located within the firebox, a feed system for moving combustible pellets to the pellet burner and an ash pan for receiving ashes from the pellet burner. The pellet burner includes a horizontal surface having an elongated combustion zone defined by a plurality of primary air openings in the burner surface, and a feed surface adjacent to the combustion zone. The feed system moves a thin layer of combustible pellets across the feed surface into the combustion zone. An air plenum surrounding the feed surface of the pellet burner supplies combustion air upwardly through the primary air opening and the layer of combustible pellets. The air plenum maintains the pellets relatively cool until they reach the combustion zone. Ashes drop off an edge of the burner surface into an ash pan. An artificial log set and a log support member fabricated of refractory fiber material define a secondary combustion cavity above the pellet burner.

Abstract: A solid fuel burning space heating appliance comprises a combustion chamber including front, side and rear walls, a top and a bottom. An apertured grate arrangement is provided in the combustion chamber for supporting solid fuel. An ash collecting region is located under the grate arrangement, with an air inlet for providing combustion air. A first air outlet in the combustion chamber is located below the grate arrangement, and a second air outlet in the combustion chamber is located above the grate arrangement. An air diverting arrangement is provided for selectively diverting air from the air inlet between the first and second air outlets. A glass cleaning system provides a vertical curtain of air over the interior surface of a glass panel. The glass cleaning system includes an air supply adjacent one side wall, an air reservoir connected to the air supply and a dam defining a tapered outlet slot for providing the curtain of air from the air reservoir.

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: A wood stove with glass panels for viewing of the fire therein includes a glass cleaning system with a number of features which in combination effectively prevent soot and creosote buildup. A uniform curtain of hot air is directed downwardly over the glass panels to maintain the interior surface at an elevated temperature and form a barrier to prevent soot and creosote buildup on the glass panels. The curtain of hot air is supplied by a system of interior manifolds, including a first air reservoir manifold and a second manifold positioned above the glass panels for reducing turbulence and forming a uniform laminar curtain of air. Hot air is delivered symmetrically to the air reservoir manifold from side manifolds. In addition, the glass cleaning system includes dual pane glass to help maintain the glass interior at an elevated temperature and andirons to prevent the wood from blocking or deflecting the curtain of hot air.

Abstract: Solid fuel heating appliance having high thermal efficiency and low levels of polluting emissions. The heating appliance includes an insulated secondary combustion chamber where a mixture of exhaust gases from the primary combustion chamber and secondary air is burned. A catalytic igniter is provided in the secondary combustion chamber to lower the ignition temperature of the unburned volatile gases from the primary combustion chamber. Regenerative feedback structure is provided in heat exchange relationship with the exhaust from the secondary combustion chamber to preheat the mixture entering the secondary combustion chamber, catalytic igniter, and the regenerative heat transfer assure substantially continuous combustion within the secondary combustion chamber even when conditions in the primary combustion chamber change.

Abstract: Exterior retrofit system for attachment to wood or coal-burning stoves including a secondary combustion chamber and a catalytic igniter. The secondary combustion chamber is lined with refractory material and is arranged to preheat flue gases emanating from the woodburning apparatus before ignition at the catalytic igniter. The refractory walls have an undulating structure to increase mixing and residence times for more complete burning. Provisions are made for introducing additional combustion air into the secondary combustion chamber. Combustion performance is improved resulting in reduction of cresote deposits and particulate emissions and reduction in the amount of fuel consumed for a given heat output. The retrofit unit is self-contained and requires no permanent or complicated modification to the stove. This system also has application for use on the interior of a stove, both as a retrofit and as the basis for a specifically designed stove.

Abstract: Woodburning heating apparatus including a catalytic igniter for increasing heating efficiency and reducing polluting emissions. The apparatus includes a secondary combustion chamber in gaseous communication with a primary combusiton chamber. The secondary combustion chamber is lined with a refractory material and includes a perforate catalytic igniter through which combustion gases from the primary combustion chamber flow. The secondary combustion chamber further includes refractory baffles arranged to enhance mixing of the combustion gases and located to re-radiate heat onto the catalytic igniter. Preheated secondary combustion air enters the secondary combustion chamber so that the combustion gases are more completely burned to improve heating efficiency and reduce emissions.

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.