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.

Apparatus for capturing heat from a stove to enable it to be transferred to a central heating system is disclosed. The apparatus comprises an air-water heat exchanger, the heat exchanger having an air side and a water side and being operative to transfer heat between air on the air side and water flowing in channels in the water side. The apparatus includes an air duct through which air heated by a stove can pass by convection to contact the air side of the heat exchanger and control means operable to control the amount of air flowing to the heat exchanger. The control means may include a fan that can be operated to direct the flow of air to the heat exchanger.

An air-conditioning apparatus for air conditioning indoor environments has a containment structure having a casing delimiting a first compartment and a second compartment. A pellet stove configured to operate in heating mode and provided with a first duct for movement of combustion air in input to the pellet stove is housed inside the first compartment. A monoblock portable heat pump configured to operate in heating and/or cooling mode and provided with a second duct for movement of heated air in output from the monoblock portable heat pump is housed inside the second compartment.