Properties:

A device capable of producing heat from gas, liquid fuel, or an electrical heating element designed for permanent installation in sheet metal ducts of a forced air circulating system. It consists of (1) a finned, steel burner tube, a combustion air blower, a control panel, and a constant level fuel supply system or (2) a device having a heating element which when connected to an electrical source, directly imparts heat. It may be provided with a flanged outer casing to facilitate mounting in planned or existing duct work. Circulation of the heated air is achieved by use of a blower or fan not integral with the heating unit.