Back Draft Dampers
FAMCO Reversible Back Draft Butterfly Damper with Wall Vent. Reversible Air Flow direction - Air Intake or Exhaust. Galvanized or Aluminum Vent. 4" thru 12" Duct.
FAMCO Back Draft Damper in Connecting Sleeve. Opens with Normal Air Flow - Gravity Close. No Springs or Hinges. 4" thru 20" Duct
Continental Fan Manufacturing Back Draft Dampers. Foam gasket prevents air leakage. Back Draft Damper blocks and controls draft. 4" thru 16" Duct sizes available.
Back Draft dampers are commonly installed in fan exhaust systems to prevent a back draft of outside air when the fan is off. The damper is either a Spring Return type for both horizontal and vertical mounting or Gravity Return used in vertical venting only. Air Pressure or "out draft" opens both types of Back Draft Dampers. These Dampers are of a flat split plate "butterfly" design. The Back Draft damper reduces energy loss and maintains pressurization of the area