RLY series of fuel burning hot air stove burning through the burner, resulting in high temperature gas. With the aid of the hot air furnace with the enhanced heat transfer measure, the heat conduction to the heated air is heated, and the temperature of the high-temperature gas is reduced to 250 degrees after the heat emission is reduced to the atmosphere. The air that needs to be heated is sent to the hot blast furnace and the temperature is raised to the rated value through the selection of the blower.