51CVD / 51CHD Type C Dynamic Fire Damper (Sq./Rect.)

The 51CVD/51CHD is UL/ULC certified for use as a 1-1/2 hour dynamic fire damper in HVAC systems.

The 51CVD/51CHD is designed for installation in fire-rated wall and floor assemblies using square or rectangular ductwork in systems where fans are not shut down on fire alarm activation. Unlike static fire dampers, dynamic fire dampers are tested and rated to close reliably against live airflow, making them the required choice for systems that maintain fan operation during a fire event. The Type C configuration locates the blades entirely outside of the duct airflow path, minimizing airflow resistance during normal system operation. The optional HP external sealing extends suitability to medium and high pressure duct systems up to 6" w.g. The interlocking curtain blade closes under spring tension when the fusible link releases.