Air and smells leak in around a window AC unit
- Where I am
- Hot air, bugs and outside smells slip past the unit.
- Where I want to be
- A tight fit around the AC.
- What's in the way
- The side panels and the gap between the unit and sash don't seal.
Try this first, free: Hold a strip of toilet paper around the unit. See where it flutters.
The fix
- Make sure the unit is held the way the manual says. Don't move it by yourself if it feels heavy.
- Press foam weatherstrip or window AC insulation foam along the gaps by the panels and the sash.
- Add the sealing panels that come with the unit, or foam board cut to fit.
- Look for gaps again with a strip of toilet paper.
What this won't fully fix: Foam closes the gaps. It won't stop noise or all of the outside smells.
Safety first: Window AC units are heavy and can fall. If it looks loose, ask the landlord or a helper rather than adjusting it alone.
Moving out: Peel the foam off and wipe the sill and frame clean.
What to get
These open an Amazon search, so you can pick the one that fits. As an Amazon Associate I earn from qualifying purchases.