Dayton gas-fired duct furnaces are designed to heat commercial, industrial and residential spaces. These gas-fired duct furnaces are capable of exchanging a large amount of heat with clamshell-style heat exchangers, providing an input capacity of 350000 BtuH. They are ETL-certified, providing safe operation with advance safety features. Direct spark ignitor provide open combustion and aluminised steel heat exchangers provide efficient heat exchange. Choose from a wide range of indoor duct furnaces, available in 37 and 40 inch on Raptor Supplies.