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 Direct Current (D.C.) fan motor control system for an air cooled thermoelectric power generator. This electronic control system addresses the unique challenges that exist when thermoelectric generator (TEG) modules are used in a gas fireplace appliance to use D.C. fans as the primary air circulation element. Ideally, it is necessary to generate sufficient voltage for a fan motor while maximizing the efficiency of the overall system to permit the surplus energy generated above that required for the fan motor to be used to charge batteries, including a cellular phone handset battery. DC to DC switching converter techniques are used to manage the surplus energy available. A microcontroller based supervisor will monitor the TEG output voltage and determine when an electromechanical latching relay supplying power to the fan motor should be switched to the output of the DC to DC step down (buck) converter for maximum efficiency. The microcontroller also supervises a DC to DC step down converter assigned to charging a cellular phone by disabling the cellular handset charging function when the TEG output voltage is insufficient to maintain the fan and the cellular handset charger, thus prioritizing the fan motor function as the highest priority for the best reliability.

A Direct Current (D.C.) fan motor control system for an air cooled thermoelectric power generator. This electronic control system addresses the unique challenges that exist when thermoelectric generator (TEG) modules are used in a gas fireplace appliance to use D.C. fans as the primary air circulation element. Ideally, it is necessary to generate sufficient voltage for a fan motor while maximizing the efficiency of the overall system to permit the surplus energy generated above that required for the fan motor to be used to charge batteries, including a cellular phone handset battery. DC to DC switching converter techniques are used to manage the surplus energy available. A microcontroller based supervisor will monitor the TEG output voltage and determine when an electromechanical latching relay supplying power to the fan motor should be switched to the output of the DC to DC step down (buck) converter for maximum efficiency. The microcontroller also supervises a DC to DC step down converter assigned to charging a cellular phone by disabling the cellular handset charging function when the TEG output voltage is insufficient to maintain the fan and the cellular handset charger, thus prioritizing the fan motor function as the highest priority for the best reliability.

A solid fuel heating apparatus (1) comprising a combustion chamber provided with a glass door (4) opening to the outside, an intake device (11) for the intake of outside combustion air into said chamber, an outlet duct for the burnt gases (2) and a sealed preheating enclosure for preheating the combustion air, conveying said air to the combustion chamber, connected at a first end to the intake device (11) and ending at a second end with a plurality of openings (9) releasing the air preheated by the preheating enclosure into the combustion chamber, characterized in that the preheating enclosure consists of a set of sealed heat exchanging pipes containing the combustion gases and the burnt gases (3, 8, 12, 15, 17, 18, 19), ending with the abovementioned openings (9), which are variable in size and are arranged in such a way as to modulate the flow of preheated air released into the chamber, enclosing the flame and combustion area in the natural conical shape of said chamber.

A solid fuel heating apparatus (1) comprising a combustion chamber provided with a glass door (4) opening to the outside, an intake device (11) for the intake of outside combustion air into said chamber, an outlet duct for the burnt gases (2) and a sealed preheating enclosure for preheating the combustion air, conveying said air to the combustion chamber, connected at a first end to the intake device (11) and ending at a second end with a plurality of openings (9) releasing the air preheated by the preheating enclosure into the combustion chamber, characterized in that the preheating enclosure consists of a set of sealed heat exchanging pipes containing the combustion gases and the burnt gases (3, 8, 12, 15, 17, 18, 19), ending with the abovementioned openings (9), which are variable in size and are arranged in such a way as to modulate the flow of preheated air released into the chamber, enclosing the flame and combustion area in the natural conical shape of said chamber.

A heating apparatus can include a fire cage defining a cage space containing heated fuel. The heating apparatus can also include a container configured to be supported by the fire cage at a container position, wherein the container is above at least a portion of the cage space. The container can be designed to hold burning fuel above the heated fuel. Also, a heating apparatus can be arranged to form a food grill, and the heating apparatus can be rearranged to form a fire cage configuration. A thermal store can be placed in a heat collecting position on a side of the fire cage in a first location to heat the thermal store. The thermal store can be moved away from the fire cage and can be positioned in a second location away from the fire cage to emit thermal energy to heat air around the second location.