Backdraft Dampers - Steel Frame - BD-300 Series

The BD-300 series backdraft dampers mount vertically to allow horizontal airflow and prevent reverse airflow. Dampers in this series: BD-300 with a flange on intake, BD-320 with a flange on discharge and BD-330, which does not have a flanged frame. All dampers in this series open by air pressure differential and close by gravity. Pressure: Up to 2 in. wg (0.5 kPa) Velocity: Up to 1500 fpm (7 m/s) Temperature: Up to 180°F (82°C) Accessory to wall fans and centrifugal inline fans