I live in an apartment and have a central air system but my main bedroom always stays about 10-15 degrees hotter than the rest of the apartment. I reached out to my landlord about this problem and she just brushed me off, so I called out an AC company & they said that the duct work was too small for the bedroom (they can't do anything without landlord approval) so here I am looking for a window AC.

I have a pretty large & odd shaped vertical opening window measuring in at about 50" wide and 12 1/2" tall. I've searched high and low for a window AC unit to fit those measurements, but continue coming up short. Any ideas on how I could get a standard window unit to fit in & stay?

I should also mention that I obviously rent & the frame is metal, so I can't screw or nail anything in.

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That is a really wide window.

At just 12 inches tall you won't be able to fit any sort of window unit. Even 6,000 btu models are usually 12.5 inches tall. If you can find a short enough model then great but then you'll have to contend with finding a wide enough accordion curtain or just fill the void with cardboard.

An alternative option is a portable A/C which sits on the floor and exhausts out the window using a vent tube.

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  • Yup, these fit just about anything. I've got one of those behind me because there is a solar screen on the window and thus nothing can be mounted outside. – Loren Pechtel Mar 13 at 4:03
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    I've got one of those portable ACs. It really pays off to add another duct for the air intake so it doesn't depressurize the room and suck hot air in. – bobflux Mar 13 at 11:30
  • Where does condensation go in this portable AC units? – RonJohn Mar 13 at 11:49
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    @user2357112supportsMonica it is a plastic piece that comes with the A/C unit. Open your window slightly, put the plastic piece across the opening, and fit the exhaust duct in the hole in the plastic. I used one of these for years in a similiar situation with small windows that wouldn't open enough for a proper window unit. Not the most efficient setup, but does the job – psubsee2003 Mar 13 at 12:36
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    @RonJohn The condensation is usually collected in a tray at the bottom of the unit, which requires any of: manually emptying when the unit detects that it's full and shuts off, a tube to allow the condensate to be evacuated to somewhere else, and/or the portable A/C to be designed to flow unconditioned air over the condensate tray in an attempt to re-evaporate it into the room. I'd note that there are also units which can sit outside, rather than inside, but those are much more likely to be stolen, as the expensive portion is outside, obvious, and not secured. – Makyen Mar 13 at 19:43

There are "saddle" or "over the sill" window units that might fit nicely in this window.

NOTE make sure the unit you buy will fit through the fully open window during installation. See if you can remove the lower sash or both of them to aid installation. Or if the window has top limiters (screws or blocks in the channels) that can be temporarily removed to open it further for installation (unlikely for a ground floor but have a look.)

These A/Cs are good for rentals as they don't require mounting brackets or screws. There will be a narrow gap on the sides of the unit that you'll have to fill. There are foam strip kits you can buy to do that, and/or use strips of wood or plastic. With these units it's easy to open the window when not in use and for that reason you should not fill the gaps by taping/gluing anything to the window. Make sure the wall is not thicker than the saddle width of the machine.

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  • How tall are these units, can it even fit in the window to get saddled? – MonkeyZeus Mar 12 at 19:03
  • I'm seeing 15 inches tall for 6k btu models – MonkeyZeus Mar 12 at 19:28
  • Good point. Edited answer. – jay613 Mar 12 at 19:38
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    See if you can remove the lower sash to aid installation. Or if there are top limiters that can be temporarily removed to open it further for installation (unlikely for a ground floor but have a look.) – jay613 Mar 12 at 20:04
  • If you add that into your answer then I would be inclined to upvote. I didn't even think of that option. – MonkeyZeus Mar 12 at 20:05

Picture below may help. Masking tape may help to keep the plywood in place, if it is your option. Also, you can use rigid foam (wrapped in plastic) at the bottom to level the window track.

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