Does anyone know the difference between a window and a wall air conditioner? The window unit is much cheaper. I see several units here that appear to be window units and through the wall...there is no "sleeve" on them. Thank you!

  • 1
    Lots of wall units come with a remote control so they can be put through an opening high on a wall. This feature will increase cost some. The wall units are probably better made because they are being sold to more demanding people who have a purpose built opening for them which requires more planning and resources. Jun 1, 2017 at 0:25

4 Answers 4


Apparently window and wall a/c units are not interchangeable, although I don't have the details of the difference.

EDIT Window units are designed to take advantage of the fact that a window is a thin partition; vents on the outside of the a/c case can be close to the inside part of the a/c unit, but still be outside (where they have to be). This may allow the window units to be cheaper. In contrast a wall can be 6" thick or more; wall units must have all vents close to the back of the unit. BTW I always thought that the vents in the side of a window unit were for intake of air at ambient temperature to then be directed through the condenser coil at the back plane of the unit to be exhausted out the back (now hotter than ambient), but in fact some of the side vent area may also be used for expelling air which cools motors. It could be that in a window unit the venting on one side is devoted to intake of air for the condenser coil and the venting on the other side is for exhaust. This would prevent the hot exhaust air being pulled in the intake for the condenser cooling air.

Window ACs vs. Through-the-Wall ACs

It's easy to compare window and thru-wall ACs, because they're similar in cooling capacity and size, but through-the-wall units tend to be slightly more efficient because they create an airtight seal in the room.

The major differences between these ACs involve installation and venting. Window ACs fit through a window and don’t require permanent installation, while thru-wall ACs are actually built into the wall—making them popular in rooms without windows or for people who prefer to leave their windows alone.

Wall air conditioners typically only vent warm air through the back of the unit, while window ACs vent from the sides and back. For this reason, window and thru-wall models are not interchangeable (even if they're the same size). In most cases, if a window unit vents out its side, the wall will block the vents and cause overheating. Select window AC models can be installed through a wall, but only if they have a slide-out chassis wall sleeve. Read more on wall sleeves.

https://www.sylvane.com/thru-wall-air-conditioner-buying-guide.html#vs .


If you have a window AC with slide our chasses. Check the distance from the chassis front to the fist vent. (Say 8 inches) Now measure your wall thinkness. If less that the first measurement (8 inches in my case) then installing installing the chassis through the wall and then sliding in the AC unit should work just fine. Keep in mind that a platform of 2 x 4"s (or other) needs to from out the AC Chassis. In the end be sure to seal the chassis from out side air.

THAT SAID! CAUTION If you have vinyl siding the vents on the AC unit may be too close to the siding may warp the siding.

  • Hello, and welcome to Stack Exchange. It's a bit hard to understand your answer with all the misspellings; you may want to do a bit of editing to make it clearer. May 27, 2018 at 1:23

I put an inexpensive window unit high on a wall without knowing the could be a problem. The wall is standard 2 X 4 with drywall both sides. It has been fine for about 10 years. My problem is the subdivision does not permit window units. It cools a room on the garage. It is between the room and the garage; it draws air for the condenser from the garage and exhausts hot air into the attic. I built a plenum of 1/4" paneling to do this. Can't remember any details, but it was nothing unusual. It has a remote , I thought now, they all had remotes .


I have actually put a "dryer vent" A/C unit (like this one through the wall (only the hoses went).

It was a double vent unit as well. I had to construct a hood for it with window netting, but it worked well enough. Just be sure to also add a drain hose so it can run outside or you'll be dealing with the drain pan as well.

Not the answer you're looking for? Browse other questions tagged or ask your own question.