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 bell mouth includes an upstream body including an upstream-side opening formed to allow air introduced from an air supply duct to pass through and an upstream measurement portion connected with a differential-pressure acquisition device that uses pressure of the air in the upstream-side opening, in which the air supply duct guides the air into a water-heating device from the outside, a differential-pressure generation part that is located downstream of the upstream body with respect to a flow direction of the air and that has a structure that reduces the pressure of the air passing through the differential-pressure generation part, and a downstream body including a downstream-side opening formed to allow the air passing through the differential-pressure generation part to pass through and a downstream measurement portion connected with the differential-pressure acquisition device that obtains a difference between the pressure of the air passing through the downstream-side opening and facing toward a blower of the water-heating device and the pressure of the air in the upstream-side opening.

A bell mouth includes an upstream body including an upstream-side opening formed to allow air introduced from an air supply duct to pass through and an upstream measurement portion connected with a differential-pressure acquisition device that uses pressure of the air in the upstream-side opening, in which the air supply duct guides the air into a water-heating device from the outside, a differential-pressure generation part that is located downstream of the upstream body with respect to a flow direction of the air and that has a structure that reduces the pressure of the air passing through the differential-pressure generation part, and a downstream body including a downstream-side opening formed to allow the air passing through the differential-pressure generation part to pass through and a downstream measurement portion connected with the differential-pressure acquisition device that obtains a difference between the pressure of the air passing through the downstream-side opening and facing toward a blower of the water-heating device and the pressure of the air in the upstream-side opening.

The present application discloses a combustion apparatus including: an air supply/exhaust port formed such that an air supply passage surrounds the outside of an exhaust passage; and an air supply port in which an air supply passage is formed. This combustion apparatus is configured such that in a case where this apparatus is installed in the double-pipe system, the air supply passage of the air supply port is closed, whereas in a case where it is installed in the separate-pipe system, the air supply passage of the air supply/exhaust port is closed. The combustion apparatus includes: a supplied-air temperature sensor; and a guide member, which is located near the air supply passage of the air supply/exhaust port or the air supply passage of the air supply port, and by which air flowing into the space in the housing is guided to the supplied-air temperature sensor.

The present application discloses a combustion apparatus including: an air supply/exhaust port formed such that an air supply passage surrounds the outside of an exhaust passage; and an air supply port in which an air supply passage is formed. This combustion apparatus is configured such that in a case where this apparatus is installed in the double-pipe system, the air supply passage of the air supply port is closed, whereas in a case where it is installed in the separate-pipe system, the air supply passage of the air supply/exhaust port is closed. The combustion apparatus includes: a supplied-air temperature sensor; and a guide member, which is located near the air supply passage of the air supply/exhaust port or the air supply passage of the air supply port, and by which air flowing into the space in the housing is guided to the supplied-air temperature sensor.

The present disclosure discloses a combustion chamber and a combustion apparatus. The combustion chamber includes: a first surrounding plate located on an outer side and a second surrounding plate located on an inner side. A combustion cavity is defined by the second surrounding plate. The first surrounding plate and the second surrounding plate are spaced apart from each other to define at least one air duct in communication with the combustion cavity. Each of the at least one air duct has an air inlet hole formed in the first surrounding plate, and an air outlet hole formed in the second surrounding plate.