Turbulence System and Steam Extraction: Turbulence is normally fitted to all but the initial (feed end) zone or zones of the oven and is completely independent of the heating system. It is recirculatory to give the maximum heat loss from the baking chamber. The system comprises an extraction duct with openings into the baking chamber, a turbulence fan in a steel case having impellers with air-cooled bearings driven by an electric motor, mild steel delivery ducts with turbulence control dampers, leading to the top and bottom turbulence tubes in the baking chamber. The turbulence tubes are fitted to improve the heat transfer to the product, the velocities not being high enough to disturb flour or sugar dust on the product.

The ratio of the top and bottom turbulence can also be controlled ny dampers on the burner side of the oven. The ductwork includes a spill over outlet with linage connections for a steam tube with control damper. Should the turbulence system not be specified , then each zone is provided with its own extraction fan mounted over the heater bay and extracting from the chamber. The extraction rate is varied by means of a damper. Additionally, a small steerage extraction fan is fitted at the delivery end to extraction velocity slot built in the end to prevent under spillage of baking chamber air into the bakery.