Abstract: A central heating installation provided with a hot tap water circuit for domestic usage includes a heating apparatus having an enclosure the inner portion of which is provided with a burner, notably a gas burner, and on which is possibly wound or a heating circuit duct extending thereafter through a fin assembly situated in the upper portion of the enclosure, along the path of travel of the hot gases, the heating circuit, when extending through the fin assembly, being provided in the shape of a plurality of flattened tubes connected to one another by elbows and the hot tap water circuit being provided in the form of a tube having the shape of a hairpin or of a pipe coil and placed inside the flattened tubes where they extend through the fin assembly.