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 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.

A furnace including a combustion chamber for burning fuel can have increased fuel burning efficiency, increased heating efficiency, and decreased harmful emissions of combustion byproducts. A combustion air delivery system delivers primary and secondary combustion air to the combustion chamber. Primary and secondary combustion air may be delivered at amounts that increase burning efficiency. An amount of secondary combustion air can be controlled by a valve system. A heat transfer device efficiently transfers heat from products of combustion for heating an enclosed space.

A wood burning heater is presented. The wood burning heater has an external box housing that has an inside, an outside, a front, a back, a first side, a second side and a bottom. On the inside of the wood burning stove is an inner fire box. The inner fire box has an opening that coincides with the front of the external box housing and a blower device that extends from the external housing box.

An appliance comprising a firebox, a first air duct and a room air chimney. During operation of the appliance heated room air adjacent to a viewing pane or the screen and heated room air from the first air duct is received within the chimney. The heated air within the chimney rises toward an open upper end causing the chimney to draw additional room air from adjacent to the viewing pane or screen.

A furnace including a combustion chamber for burning fuel can have increased fuel burning efficiency, increased heating efficiency, and decreased harmful emissions of combustion byproducts. A combustion air delivery system delivers primary and secondary combustion air to the combustion chamber. Primary and secondary combustion air may be delivered at amounts that increase burning efficiency. An amount of secondary combustion air can be controlled by a valve system. A heat transfer device efficiently transfers heat from products of combustion for heating an enclosed space.

A furnace including a combustion chamber for burning fuel can have increased fuel burning efficiency, increased heating efficiency, and decreased harmful emissions of combustion byproducts. A combustion air delivery system delivers primary and secondary combustion air to the combustion chamber. Primary and secondary combustion air may be delivered at amounts that increase burning efficiency. An amount of secondary combustion air can be controlled by a valve system. A heat transfer device efficiently transfers heat from products of combustion for heating an enclosed space.

A furnace including a combustion chamber for burning fuel can have increased fuel burning efficiency, increased heating efficiency, and decreased harmful emissions of combustion byproducts. A combustion air delivery system delivers primary and secondary combustion air to the combustion chamber. Primary and secondary combustion air may be delivered at amounts that increase burning efficiency. An amount of secondary combustion air can be controlled by a valve system. A heat transfer device efficiently transfers heat from products of combustion for heating an enclosed space.

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.

An appliance comprising a firebox, a first air duct and a room air chimney. During operation of the appliance heated room air adjacent to a viewing pane or the screen and heated room air from the first air duct is received within the chimney. The heated air within the chimney rises toward an open upper end causing the chimney to draw additional room air from adjacent to the viewing pane or screen.