Abstract: A combustion system includes a primary combustion chamber divided into left and right sides by fuel-retaining standards defining a canyon or void extending into a secondary combustion chamber is provided. The floor of the primary combustion chamber and the fuel-retaining standards direct the burning solid fuel toward the lower part of the canyon, while at the same time retaining the non-burning solid fuel on either side of the fuel-retaining standards. The combustion system further includes an air delivery system having a lower air tube supplying high and low velocity air and an upper air tube. The lower air tube is positioned proximate to a firebox floor, while the upper air tube is positioned within the secondary chamber. Automatic air setting mechanisms are provided so that proper air settings can be maintained during various phases of a fire.

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: A fireplace with a cooling air passageway within the fireplace housing that maintains the forward portion of the housing top wall cool during operation. The fireplace includes a combustion chamber, a flue, and an outer housing that encloses the combustion chamber. Plenums formed between the walls of the outer housing and the combustion chamber walls are used to circulate room air to keep the housing cool. Disposed within a forward portion of the upper plenum above the combustion chamber is a passageway constricting baffle. The baffle constricts the cross-sectional area of the upper plenum through which the cooling air flows and forces the cooling air flow upwardly against the underside of the housing outer top wall, thereby cooling this portion of the housing which typically is difficult to keep cool. The fireplace also includes a baffle which directs cooling air outlet from the upper plenum to a venturi passageway in communication with the flue.

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.