# Insulation surrounding a through the wall AC unit



## stuvwxyz99 (Aug 12, 2012)

I live in an apartment, and I renovated before moving in. My contractors installed new AC units in pre-existing through-the-wall sleeves. Per the pic below, there is an extensive gap between the units and the wall sleeve (currently filled by some insulating material), and another gap between the sleeve and the masonry. 

Last winter, the area around this unit was very cold and drafty. Any suggestions on how this could be improved?


----------



## Desertdrifter (Dec 10, 2009)

First question, is the space where the insulation is watertight?


----------



## joecaption (Nov 30, 2011)

Do you own this building?
Why where they allowed to install the wrong sized unit?
That should have been a slip fit with no gaps.
May have to just picture frame with some base board moulding.


----------



## stuvwxyz99 (Aug 12, 2012)

Thanks for the responses. There is no water coming in (there is a grille on the outside wall). I own the apartment, but its a large building of about 200 apartments. A New York City co-op if you are familiar with that set-up (essentially, I am a shareholder in the company that owns the building). 

There is a cover which I removed to get the picture. Cosmetically, it looks fine once the cover is on. The AC unit was my purchase. When I bought the apartment, there was a unit installed which was old, so I got the latest model - same manufacturer (Friedrich) and same size. I (wrongly) assumed that the sleeve was for this size model. 

Does it make sense to have someone put a new sleeve in? Since the wall opening is bigger than the sleeve would be, would that gap be filled somehow? Maybe this post belongs somewhere other than in Insulation.


----------



## iLikeDirt (Apr 27, 2014)

For a quick and dirty repair, you could just fill those gaps with canned spray foam. It'll insulate and air seal. If that area is covered up anyway by trim, than that might even suffice as a permanent fix. No reason to make it unnecessarily complicated.


----------



## stuvwxyz99 (Aug 12, 2012)

Thanks. So there are two gaps. #1 is between the AC and the sleeve. #2 is between the sleeve and the masonry. If I spray foam gap #1, how hard will it be to remove the AC from the sleeve at a later date?

Spray foam for gap #2 seems a good idea though.


----------



## iLikeDirt (Apr 27, 2014)

Once the foam has cured, you can pull it off with your bare hands or cut it off with a knife. If it's stuck to something plastic, you may have to scrape or sand the rest off. It's not too bad.


----------

