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Sealing Air Ducts with mastic

Zach | Posted in Energy, Heating & Insulation on

I want to seal the metal air ducts in my crawl space with mastic. Can I run my A/C right after I’ve applied the mastic?  It’s summer in North Carolina and I’m not sure how long I can go without running the A/C.

Replies

  1. florida | | #1

    I'd let it dry for at least 4 hours before running the AC.

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