This paper presents a new air flow control system which provides uniform air circulation for a wood drying process to improve drying efficiency and reduce energy consumption.The control system involves 180° rotation control of rotary fans to reverse the direction of the air flow and air flow control to channel the air through the heaters.The system was installed and compared with a conventional drying system in a commercial lumber mill.The new air control system was found to save up to 60% of the energy cost and reduce the lumber drying time by two days.In addition,the new control system eliminated the conventional air flow device which required an extra 0.5 m of ceiling space.