The Hart Cooley 3800-12-01 is an adjustable round butterfly damper designed for use in residential and commercial HVAC air distribution systems. This damper is built to work with 5400 and 6400 Series collars and T-bar diffusers, making it a reliable choice for HVAC technicians who need a proven, compatible solution for controlling airflow in ceiling and wall installations. The unit measures 12 inches in duct size, with an outer diameter of 11 and 11/16 inches and a depth of 1 and 31/32 inches. The blade thickness is 1/4 inch, giving it the structural rigidity needed for dependable long-term use. Constructed from steel and finished in Golden Sand Enamel, this damper resists corrosion and blends cleanly into standard ceiling grid and diffuser assemblies. The butterfly damper design allows HVAC professionals to adjust airflow volume quickly and precisely, helping balance air distribution across zones in both new construction and retrofit applications. The round configuration is ideal for round neck diffusers and collar fittings commonly found in residential forced-air systems and light commercial HVAC setups. HVAC technicians, sheet metal contractors, and mechanical installers rely on Hart Cooley dampers for their consistent fit, durable materials, and compatibility with standard diffuser systems. This model is part of the 3800 Series, which is known for straightforward installation and accurate airflow control. Whether you are balancing a multi-zone system or replacing a worn damper in an existing installation, the Hart Cooley 3800-12-01 delivers the performance and compatibility trade professionals expect.
The Hart Cooley 3800-12-01 provides reliable airflow adjustment in a 12-inch round configuration, built from steel with a Golden Sand Enamel finish and designed for direct compatibility with 5400 and 6400 Series diffuser collars and T-bar systems.