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Best wrap to insulate through-the-wall AC

Recently installed a through-the-wall AC in rear porch. Installers stuffed fiberglass into wall all around, caulked well inside and out, and we bought a metal cover for outside and a thick cloth cover for inside. Construction is mid-60s frame, inside walls are wood pine panels.

However, being all-metal, the AC unit conducts alot of cold, which I think might be perceived as a draft--as warm room air moves towards cold around AC especially around the AC perimeter where it comes out of the wall.

I was wondering what kind of wrap (maybe 4-6" wide) I could use to wind a few times around at the wall before I put the inside cloth cover on. (and also wouldn't look too junky like padded-tape, etc. (I also intend to affix a piece of styrofoam to the AC front under the cloth cover.)

Thanks for any answers.


  • TechmanTechman Member Posts: 2,144
    edited October 2011

    How to seal a t-t-w Room AC and make it look good at the same time ? Nice try! Is this a "sleeve " in the wall and then you slide the AC unit into the sleeve? Or is this a RAC( room AC) put into a hole in the wall? Either way ,that precieved draft ,is more then likely ,a draft! Covering and sealing the outside of the AC w/ a metal/wood/plastic cover to block the outdoor air/wind from finding it's way in, is what you are looking for.I think there should be air circulation thru the inside of the inside part of the AC to prevent moisture damage. If sealed to good,you can trap  moisture inside the AC.The same goes for outdoor units of Central AC systems.
  • D107D107 Member Posts: 1,723
    edited October 2011

    Thanks, this is a Friedrich CP10F10 10K btu. (see attached. it's a window unit installed through the wall.) We already have an outside metal cover. I was concerned about moisture buildup too with an inside cover as well. So how to ensure air circulation with the inside cover on too-- it is cloth so perhaps it will breathe. Maybe not put the styrofoam on in addition.

    The draft seems to come from the perimeter of the AC, so wrapping some kind of tape around that shouldn't affect air circulation within the unit.

    (Note that the expandable 'wings' of the AC were not installed since it's not in a window.)
  • TechmanTechman Member Posts: 2,144

    Usually w/ RAC's put into wall's, the wall is the "draft" problem.When the hole was cut into the wall the open bay's (top, bottom, and sides) would have to be "sealed" to prevent a draft comming from the interior of the wall itself. Just like the draft you get around/thru the electrical outlets.Another thing,usually w/ RAC's (instead of thru-the-wall units) in the wall , usually on the outside of the RAC the condensor air opening's "into"  the unit are partially blocked by the thickness of the wall itself. Sheetrock,studs,outside sheathing ,and exterior finish and stuff like that.Is yours blocked?
  • D107D107 Member Posts: 1,723
    openings into unit

    Thanks again. re: those openings into the unit we made sure before we bought the unit that there was enough clearance for them. Luckily the wall is only 4-5" thick so there's no blockage. I guess with the outside metal cover perhaps no need to cover those air vents during the winter.

    I do recall that even the outside cover is not completely sealed so perhaps on a windy day air can get through.

    This is not mine but my elderly mother's house; the baseboard heat is right below. She has become adept at finding every draft in this 1950s house. You really only feel it if you're a foot away; so my somewhat unwelcome answer has been: then don't stand there.
  • TechmanTechman Member Posts: 2,144

    Yes! Block those air openimgs!
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