Abstract: A gas combustion apparatus including a housing having a top wall and a side wall, the top wall and the side wall defining vertical and horizontal openings, respectively, and the housing defining a combustion chamber having an exhaust opening; a burner mounted in the combustion chamber; and a vent assembly for venting exhaust gases generated by the burner to either the vertical or the horizontal opening, the vent assembly including two substantially identical vent conduits, each of the vent conduits having a central axis, a first end defined by a first continuous edge lying in a plane perpendicular to the central axis, and a second end defined by a second continuous edge lying in a plane at a forty-five degree angle to the central axis, the second ends of the vent conduits being connected together with the central axes of the conduits aligned to conduct exhaust gases between the exhaust opening and one of the vertical opening and the horizontal opening, and the second ends of the conduits being connected toget