A forced air circulation heating apparatus in which an air stream is heated at a first location in a conduit means and transported to a second location within the apparatus by the conduit means and is forced into a heating compartment and mixed with a recirculated forced air flow within the compartment. A valve or controller means can be used to vary the proportions of the heated air stream and the recirculated forced air flow which are combined within the heating compartment. The air conduit and the heating compartment can have a common wall whereby the heated air stream indirectly heats the heating compartment. A dual flow impeller fan is used to move the heated air stream and to establish the recirculated forced air flow within the heating compartment. The fan operates with a single electric motor. The heating compartment is vented to a flueway.