Can I seal basement vent?

Old 02-01-11, 09:30 AM
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Can I seal basement vent?

On the outside wall next to the Hot Water Tank and Natural Gas Furnace there are two 3" holes that lead outside. One of them has a 3" round aluminum duct whose end sits right next to the bottom of the furnace, the other hole is just open and looks like it has a small mesh screen.

On top of the Hot Water Tank there is a 3" round aluminum duct that meets with another duct coming from the furnace and they both look like they go out the roof of the house.

The open hole is letting in a lot of cold air and seeing that I am in the middle of air sealing as much as the basement that I can, I was wondering if I can seal this open hole?

Also...with all of the air sealing I think it makes sense to install a carbon monoxide detector somewhere near the Hot Water Tank and Furnace...does that make sense? I already have one on the main floor.


Old 02-01-11, 10:37 AM
lawrosa's Avatar
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No that is the make up air for the furnace and HWH. Do not close these holes. Your appliances need a proper amount of air to burn properly

Mike NJ

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