I need to install an exterior makeup air duct to provide makeup air for my new stove hood.
My house is fairly tight, and I've been making energy efficient improvements including tightening the envelope to prevent air leakage. However, I do not see a single electric damper that actually seals in the closed position. They all have sizable holes in the gasket around the pivot pin.
Is there a reason this cannot exist, or have I just not found it yet? If they don't exist, is there a better alternative than a mechanical damper?
FWIW I would prefer a rectangular damper, but I could use a round damper instead -- the duct isn't installed yet.