Abstract: The invention relates to an arrangement (1) including two burners (10), which has a common exhaust gas guiding device (2) and a common supply device (3) for combustion air. A backflow barrier (4) blocks a flow of a gaseous medium in a flow direction and is arranged in the exhaust gas guiding device (2) or in the supply device (3). The backflow barrier (4) has an opening (40) and a movable element (41) which is movable between two positions. The opening (40) is open in case the movable element (41) is in one of the two positions and closed in case the movable element (41) is in another of the two positions.

Abstract: No new matter has been added. The invention relates to a device for heating a medium, comprising a burner unit and a flame tube, wherein the burner unit generates flue gas, wherein the flame tube has a flue gas inlet, a longitudinal axis, a casing extending along the longitudinal axis, and an end face opposite the flue gas inlet, wherein the flue gas passes from the burner unit into the flame tube via the flue gas inlet, wherein a plurality of recesses are located in the casing, and wherein the recesses have different dimensions and/or are distributed asymmetrically on the casing. The longitudinal axis is in a central plane, wherein a first side and a second side of the casing are formed by the central plane, and wherein recesses on the first side have smaller dimensions than recesses on the second side.

Abstract: The invention relates to an arrangement (1) including two burners (10), which has a common exhaust gas guiding device (2) and a common supply device (3) for combustion air. A backflow barrier (4) blocks a flow of a gaseous medium in a flow direction and is arranged in the exhaust gas guiding device (2) or in the supply device (3). The backflow barrier (4) has an opening (40) and a movable element (41) which is movable between two positions. The opening (40) is open in case the movable element (41) is in one of the two positions and closed in case the movable element (41) is in another of the two positions.

Abstract: The invention relates to a heating device for heating air, having a primary heat source (10) and a heat exchanger (2). The heat exchanger (2) has an interior space (22) for receiving the primary heat source (10) and transfers thermal energy generated by the primary heat source (10) to the air. The heat exchanger (2) includes a holding element (21) for receiving an electric heating element (11) as a secondary heat source (2). The heat exchanger (2) consists of a first heat exchanger unit (201) and a second heat exchanger unit (202).

Abstract: A heating apparatus for generating a hot air flow comprises a single fan, a burner heating element and a resistance heating element. In this respect, an air passage that conducts air to be heated and a combustion air passage that leads to a burner adjoin the fan downstream, wherein a combustion air flow in the combustion air passage can be controlled by a control element associated with the combustion air passage.