I just put a window AC unit on a table in front of a window instead of hanging out of the window. The back is flush with where the screen would be so the heat is pumping outside.. but the side vents that are normally outside the house are in the house. Is there an issue with this? The AC unit is just about 1 inch too big to fit fully out the window...but the back is flush with the frame.


Kellyenter image description here

  • Hello, and welcome to Stack Exchange. Those vents are probably there for a reason, and the reason probably assumes that they'll be outside. Other than that, we probably can't say without more information (e.g. can you feel air being blown out of or sucked into these vents?). – Daniel Griscom Aug 8 '18 at 1:29
  • They suck in air, I just uploaded the post to have a picture – Kelly Ann Aug 8 '18 at 1:43

This should work, except there are some potential problems:

  • Usually a window A/C gets rid of the indoor heat by taking outside air and heating it, discharging it outside. Here, you're taking inside air and heating it (still discharging it outside). This will work, and it's exactly how single-hose indoor air conditioners work. However, it's less efficient (perhaps a lot less efficient).

  • The evaporator coil (that cools the indoor air) also condenses water, which has to be disposed of outside through a drain. It's quite possible that the normally-outside drain is now inside, and you're going to find an increasingly large puddle on your floor.

  • Your A/C will likely be noisier than it usually is (at least indoors, but that's where it counts).

So, it'll work, but there may be issues (the water one being the most immediately concerning).

  • Thank you for your input! I do have a tube taking water outside... this isn't going to be a long term thing... just trying to get through the heat wave that seems o be across all of Canada! – Kelly Ann Aug 9 '18 at 0:53

You would be better off placing the unit on a shelf or bracket outside the window with the front flush with the frame.

Most modern ACs draw inside air through a filter across the front, and blow the cooled air back into the room through a directed vent. Such a unit would work efficiently if placed outside a window. Provided, of course, that it didn't fall off its shelf and commit an injury tort below.

  • Thank you for your help! I have a tube draining the water outside. This is just a temporary solution to a relentless heat wave and is not intended to be used for very long. Just trying to take the edge off a bit! – Kelly Ann Aug 8 '18 at 15:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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