Heating appliance, esp. central heating and/or water heating systems has heat transfer unit with exhaust gas track and heating fluid track with very low heat transfer resistance, to create condensing boiler

摘要

The appliance has a heat transfer unit (2) to transfer heat carried in combustion waste gases to the heating fluid of a heating circuit coupled to the appliance. The transfer unit has an exhaust track (3) with waste gas flowing through, and a fluid track (4) with heating fluid flowing through. It also has a heat exchanger (5) with a fluid-filled basin (6). This is integrated in the exhaust track so that the gas flows through the fluid and transfers heat to it, and integrated in the fluid track, so that the heat in the basin is transferred to the heating fluid. The heating track is open, so that the fluid in the basin is part of the heating fluid, or closed, so that the fluids are separated by a heat transfer wall.