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How to seal gaps around air conditioner lines?

[email protected] | Posted in Mechanicals on

I’m trying to install a Mini-Split Air Conditioner and looking for suggestions on how to seal the gaps around the lines.

At the place where the lines come through the hole in the wall, there’re small gaps between the sleeve and the lines/pipe. I know most contractors don’t seal them. But if I really want to seal them, what material should I use here?

Another place I want to seal is the end of duct hide where the lines coming out, I want to seal the opening to keep out small animals/insects.

Thanks ahead!


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  1. GBA Editor
    Martin Holladay | | #1

    Narrow cracks (up to about 3/8 inch or 1/2 inch in width) are generally sealed with caulk.

    Wider cracks are generally sealed with canned spray foam.

  2. [email protected] | | #2

    Thanks Martin!

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