Abstract: A heating assembly for variably heating ambient air within a building. The heating assembly includes an elongated heating conduit. There may also be a plurality of heating assemblies 20 interconnected to each other to form a heating system for the building. If a heating system is employed, then the plurality of heating conduits will be interconnected to each other in such a manner as to define a common exhaust. A burner is connected to the inlet of the heating conduit. A fuel regulator is connected to the burner for providing fuel to the burner at a low fuel pressure, which defines a low heating temperature, and a high fuel pressure, which defines a high heating temperature. A vacuum device is connected to the exhaust of the heating conduit or conduits for pulling the air into the inlet and through the heating conduit to provide a negative pressure within the heating conduit during the heating of the air.