Q: I've an in-window AC unit that I've inherited for free from my previous roommate. With the weather warming up, the time when it migrates back to our window is close at hand. Trouble is, the flaps on the side of the unit (that slide out to fill the excess horizontal space when mounted in the window) are...well, pretty much busted. I can't stand running it as-is because I just bleed dollars out the window...
...our ConEd bill is astronomical during the warmer months compared to any other time of the year. I can't afford to buy a new one at the moment. Are there any inexpensive or DIY methods that are effective sealing the sides of this thing?
Asked by Evan
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Take a piece of that rigid blue insulation foam board (1" or 2") and cut it down to the size of the gaps on either side. Put a couple of coats of primer on the pieces and they'll look fine. Then fit them snugly in the gaps. Maybe a little clear packing tape on the inside to hold them in place while you lower the window, and for a tight seal.
My husband just did the following with an air-conditioner that had lost it's side flaps: Go to the local hardware store and get a piece of plexiglass cut to fit the opening. Screw it into the windows, using an electric drill to get through the plexi and metal window frame. Caulk around the edges. This is how the AC installers do it, and it was pretty easy, and cheap.