Abstract: A control system for controlling movement of damper blades in a damper housing being open and closed positions consists of a support member having a driving link movable thereon and moved through a drive means. The driving link is biased to a closed position by a spring and is moved to an open position through the drive means, which is disengaged from the driving link through a power-operated member. The drive motor and the power-operated member connected to a power source through an electric circuit which incorporates switches and sensors that will automatically cause the damper blades to close under preselected conditions and a manual-override for remote-control and for manually overriding the temperature-sensing mechanism when desired.