A heat reclaimer mounted on an exhaust-conveying flue, the flue having a flue inside surface in contact with the exhaust, the heat reclaimer including a heat-exchange assembly adjacent to and in contact with the flue. The heat-exchange assembly includes: (a) a fan for moving ambient air; (b) a chamber through which the fan drives the ambient air, the chamber defining a primary airflow direction; and (c) a plurality of heat transfer plates inside the chamber and transverse to the primary airflow direction, the plates defining airflow openings therethrough and having at least an edge in solid-to-solid thermal contact with a flue inside surface portion inside the chamber, thereby heating the ambient air with heat from the exhaust.

A solid pellet fueled heater having a base unit with forced air blowers and a dual tube chimney structure is disclosed. The dual tube chimney structure may be used to warm incoming air for distribution around the heater. The pellet heater may also include a dual auger system and multi/high speed auger motor. The dual auger may include first and second auger blades mounted on a single auger shaft having blade pitches configured to convey solid fuel in opposite directions.

A heating device, preferably for the combustion of biomass, in particular of pellets of biomass, in one aspect, includes a burner part and a heating part. The burner part includes a combustion chamber; a double-walled, internally hollow combustion-chamber wall, which has an upper opening leading above the combustion zone into the combustion chamber; a flue-gas duct which leads the flue gas downwards along the combustion chamber, wherein the flue-gas duct is followed by a heat-exchanger area including initially, a flat-tube flue-gas heat exchanger, then, a tertiary-air heat exchanger; a flue-gas ventilation stack, a radiant-heat exchanger located above the combustion chamber, a flue-gas flap at the upper end of the flue-gas duct, which, when open, connects the flue-gas duct to the stack. A flat-tube flue-gas heat exchanger of the heating part forms a heat-exchanger circuit with an exhaust-air heat exchanger with the same heat-transfer medium as the flat-tube flue-gas heat exchanger.

A solid pellet fueled heater having a base unit with forced air blowers and a dual tube chimney structure is disclosed. The dual tube chimney structure may be used to warm incoming air for distribution around the heater. The pellet heater may also include a dual auger system and multi/high speed auger motor. The dual auger may include first and second auger blades mounted on a single auger shaft having blade pitches configured to convey solid fuel in opposite directions.

A solid fuel burning cabinet circular heating appliance achieves improved emissions performance by providing a secondary air combustion path that preheats secondary combustion air. The firebox is selectively insulated such that areas of the firebox that do not preheat combustion air retain heat in the firebox while areas of the firebox that transfer heat into the combustion air transfer heat through the firebox into the incoming combustion air. The exhaust air path from the firebox to a chimney is also uninsulated to allow relatively quick heat transfer into a room in which the appliance is installed

A dual-fuel fireplace apparatus is described. In one example, an apparatus includes an enclosure having a door disposed thereon and a wood burning compartment disposed within the enclosure. The wood burning compartment has an insulated housing configured to support temperatures associated with burning of wood within the wood burning compartment. A gas burning compartment is also disposed within the enclosure and has a gas burner disposed therein. A mechanism including a motor is configured to cause movement between a first mode in which the wood burning compartment is viewable through the door and a second mode in which the gas burning compartment is viewable through the door.

A single burn rate woodstove provides primary combustion air and secondary combustion air to a combustion chamber of the woodstove. The woodstove includes a primary air inlet, a primary air outlet into the combustion chamber, and a secondary air outlet into the combustion chamber. Some embodiments of the inventions include secondary air inlet(s) for the secondary combustion air separate from the primary air inlet. Some embodiments of the invention include the same firebox sizes as known in the prior art while providing such inexpensive single burn rate woodstoves with improved emissions performance by using both primary and secondary combustion air.

A safety barrier heat exchanger for a heating appliance such as a fireplace or furnace is provided. The safety barrier heat exchanger includes a housing configured for attachment across the viewable opening of a fireplace or a barrier window of a furnace, and a plurality of optically transparent, semi-transparent or translucent safety barriers secured within the housing in spaced apart relationship to define a tortuous or serpentine passageway through which a forced bulk flow of ambient air is passed across a viewable opening or barrier window more than one time. Also provided are fireplace systems comprising the safety barrier heat exchanger.

A high efficiency wood burning furnace assembly includes an internal firebox having a door positioned therein to access an interior of the internal firebox. An exhaust throat extends through an upper wall and a grate is mounted in the internal firebox and is spaced vertically above a lower wall. A primary diffuser is mounted within the internal firebox and is positioned adjacent the front wall and the grate. A primary air supply is in fluid communication with the primary diffuser to supply air to the primary diffuser such that the air is released along an upper surface of the grate. An air conduit is mounted in the internal firebox and extends upwardly from the primary diffuser. The air conduit releases air vertically above the grate and the primary diffuser. A front wall of the internal firebox has inlets extending therethrough that are fluidly coupled to the air conduit.

A furnace including a housing and a firebox in the housing having a combustion chamber. The furnace includes a combustion air delivery system for delivering combustion air to the combustion chamber. The combustion air delivery system includes a manifold mounted outside the combustion chamber and extending vertically along the front face of the combustion chamber from a lower end to an upper end. An air blower is mounted on the manifold. The combustion air delivery system includes a primary combustion air passage for delivering air from the air blower to a primary combustion air outlet at the front face of the combustion chamber. The combustion air delivery system includes a secondary combustion air passage for delivering air to a secondary combustion air outlet positioned inside the combustion chamber adjacent the top face of the combustion chamber.