BD4 Inline 4" Butterfly Backdraft Damper | First Supply

NOTICE: Due to planned maintenance, pricing and ordering functions will be unavailable from late Friday evening, January 16 to Saturday morning, January 17.

NOTICE: Website performance may be impacted by scheduled maintenance starting at 5:00 PM CST on 1/23/26

Serving the Midwest in HVAC, Plumbing, PVF, Well & Septic and Waterworks.

Site Search

{0} items in cart

loading content

BD4 Inline 4" Butterfly Backdraft Damper

BD4 Inline 4" Butterfly Backdraft Damper

Item #FAMBD4

MFG #BD4

: The FAMCO BD butterfly backdraft damper is used as a backdraft damper for heat exchangers, air exhaust systems, solar heating systems and other HVAC air intake or air exhaust applications where a powered damper is not needed, this product is not rated for use with a dryer. This damper works in both horizontal or vertical positions and the foam seal provides minimal air leakage. Due to its unique design and aluminum blades, it opens easily with normal air flow and closes with gravity. Quality constructed from heavy-duty galvanized steel,

: Works for horizontal and vertical applications

For intake or exhaust applications

Foam seal provides minimal leakage

It opens easily with normal air flow and closes by gravity

: Damper Size4 in
Domestic / ImportDomestic
MaterialGalvanized Steel
TypeButterfly
gauge28
ManufacturerFAMCO
Manufacturer #BD4
Mounting TypeIn- Line
SeriesBD
ShapeRound

: Specification Sheet

First Mobile presents FirstSupply.com in a tile-based menu on your phone!

First InStock is our scannable label program makes it easy to stock your shop with First Supply!