Author Topic: Covering Built In Wall AC Units  (Read 435 times)


  • 5 O'Clock Shadow
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  • Posts: 4
Covering Built In Wall AC Units
« on: December 11, 2018, 09:06:02 AM »
Hello MMC. The rental my wife and I live in has AC units built into the wall, think window units but they are installed in giant holes in the wall. We also live close to the ocean in the NE so it gets very windy and cold in the winter. The past two winters I have covered them up with window film to at least seal out the draft. After spending the better part of 2018 reading through the MMM blog posts, it piqued my interest to see if we could do a better job.

Our heat is electric baseboard so it's extremely expensive. Last year we ran up north of $300 in the peak months, and this is to heat a 2 bedroom apartment, with all the AC units sealed, thermostat kept near 60, doors kept closed and heat off in rooms we aren't currently using, and us piling on blankets. This year we have a mini mustachian so we will need to keep the apartment warmer for our daughter's sake. I see AC covers for sale on Amazon and the big box stores but basic chemistry and physics says seal the leak first, then worry about insulating it, or visa versa but either way we need a seal.

I could caulk the holes where the AC units rest against the wall, pile in insulation then wrap the whole thing in window film but at some point the expense exceeds the cost savings. So here I am, asking Mustacians, what tips do you have for keeping in that sweet sweet heat? Are AC covers really effective? Am I doing the best I can with window shrink wrap?