Originally Posted By: pdacey
This post was automatically imported from our archived forum.
I’ve been finding this on most houses with vinyl siding. The vent cover has louvers. These vents are to let fresh air into the garage. The same covers were installed over the vents for the gas fired water heater closet. The louvers would only open if there is positive pressure coming from the interior, they are useless for letting air into the space.
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