Abstract: A low profile flue for a furnace, including a chamber, a vent collar and a downdraft diverter. The chamber is disposed above the heat exchanger and receives exhaust gas therefrom, the chamber being defined by a bottom wall with an opening therethrough for receiving the gas, two side walls projecting upwardly from the bottom, a top wall extending between the sides and spaced above the bottom wall, and an upper wall with the vent opening therethrough. The upper wall is connected along a forward edge to the bottom wall, connected on opposite ends to the side walls, and connected at a rear edge to the top wall. The upper wall front edge is substantially aligned with one of the vertically oriented housing sides, and the upper wall extends from the front edge over the heat exchanger at an angle on the order of 45 degrees from horizontal. The vent collar is on the chamber upper wall about the vent opening.