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 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.

Disclosed is a stove that includes a dome-shaped fire grate comprising a center, a perimeter surrounding and spaced from the center, the center being higher than the perimeter; a plurality of radial stiffening ribs extending away from the perimeter and toward the center; at least one circumferential stiffening ring extending at least partially about the center; and a plurality of ventilation holes between the center and the perimeter.

The present disclosure provides methods and systems for modulating a solid-fuel-based combustion process. A current instantaneous heat release for a solid-fuel-based heat generator is determined at a virtual sensor. The current instantaneous heat release is compared to a current firing rate demand. When the current instantaneous heat release does not correspond to the current firing rate demand, an underfire air flow of the heat generator is adjusted.

The present disclosure provides methods and systems for modulating a solid-fuel-based combustion process. A current instantaneous heat release for a solid-fuel-based heat generator is determined at a virtual sensor. The current instantaneous heat release is compared to a current firing rate demand. When the current instantaneous heat release does not correspond to the current firing rate demand, an underfire air flow of the heat generator is adjusted.

A combustion device includes a body defining a firebox, a viewing window in front of the firebox, an upper plate adjacent to a top side of the firebox, a first air passage extending from an end adjacent to a rear end of the body to a second end adjacent to a front end of the body, and a second air passage adjacent to a back side of the firebox. The second air passage has a communication opening at an end communicated with the firebox. The communication opening is at a height higher than a height of a bottom side of the firebox and lower than a height of the top side of the firebox. A burner is disposed within and adjacent to the bottom side of the firebox.

A promotion member is disposed a predetermined distance apart from an impregnation member disposed at an upstream side end of a combustion chamber, and an ignition device and a first air supply opening are prepared on an upstream side from the promotion member in an ignition space, and a second air supply opening is prepared on a downstream side from the promotion member in the ignition space. Fuel is supplied to a smooth surface of the impregnation member, and a concave part or cutout is formed in the impregnation member to house at least a part of the ignition device. A flow rate of air supplied to the combustion space through the second air supply opening becomes larger toward the downstream side. Thereby, ignitability in an evaporation type burner is improved and incomplete combustion of fuel on the downstream side of the combustion chamber is reduced.

A promotion member is disposed a predetermined distance apart from an impregnation member disposed at an upstream side end of a combustion chamber, and an ignition device and a first air supply opening are prepared on an upstream side from the promotion member in an ignition space, and a second air supply opening is prepared on a downstream side from the promotion member in the ignition space. Fuel is supplied to a smooth surface of the impregnation member, and a concave part or cutout is formed in the impregnation member to house at least a part of the ignition device. A flow rate of air supplied to the combustion space through the second air supply opening becomes larger toward the downstream side. Thereby, ignitability in an evaporation type burner is improved and incomplete combustion of fuel on the downstream side of the combustion chamber is reduced.

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.