Abstract: An air heating apparatus may be mounted on a common base and define a pair of air flow paths. The air heating apparatus may include a housing forming an outer envelope through which the air flow paths extend, with the air flow path being separate from each other at all locations in the interior of the outer envelope. The interior of the housing may be divided into two subhousings defining two separate subchambers. The housing may have inlet and outlet openings extending through the outer envelope for each of the air flow paths of the subchambers. At least two air heating assemblies may each be configured to heat air moving along a separate one of the air flow paths, the air heating assemblies being positioned in the interior of the housing with each of the air heating assemblies being positioned in a respective one of the subchambers of the subhousings.

Abstract: An air heating apparatus may comprise a housing with a path through an interior of the housing between openings in the housing. An isolating wall may divide the interior into primary and secondary chambers, and may have a transfer opening through which the path extends from the primary to secondary chambers. An air heating assembly may comprise an engine in the primary chamber, a heat generator in the primary chamber and connected to the engine, and a main heat exchanger in the secondary chamber and in fluid communication with the heat generator to transfer heat generated by the heat generator to air flowing along the path. The apparatus may include an air movement assembly configured to move air along the path and comprises a primary fan between the primary and secondary chambers to move air from the primary chamber to the secondary chamber.

Abstract: An air heating apparatus may comprise a housing with a path through an interior of the housing between openings in the housing. An isolating wall may divide the interior into primary and secondary chambers, and may have a transfer opening through which the path extends from the primary to secondary chambers. An air heating assembly may comprise an engine in the primary chamber, a heat generator in the primary chamber and connected to the engine, and a main heat exchanger in the secondary chamber and in fluid communication with the heat generator to transfer heat generated by the heat generator to air flowing along the path. The apparatus may include an air movement assembly configured to move air along the path and comprises a primary fan between the primary and secondary chambers to move air from the primary chamber to the secondary chamber.