Install An Air Conditioner In Casement Window

Keywords: ac, casement, slider, window air conditioner

Cost (in $US): 150.00
Time to Complete: 2 hours
What You'll Need: Window AC unit, plexiglass, brackets or AC support arm, screwdriver, plexigalss cutter, hammer, epoxy or industrial velcro, weather stripping, foam

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Step 1:  This article describes how to install a traditional window AC unit into a casement window or slider window (slider windows move left to right versus a traditional window that moves up and down). You may be able to find an AC unit designed specifically for a casement window, but these models tend to cost 4-5x the price of a traditional window AC unit.
Step 2:  Measure the window opening. Purchase a unit that will fit the opening. If you are installing in a slider window, open the window as far as possible to measure the width of the opening. Also measure the height of the AC unit and subtract that number from the height of the window opening. Buy a piece of plexiglass that is at least as wide as the AC unit and tall enough to fit the space from the top of the AC to the top of the window.
Step 3:  Install support brackets. Traditional window AC units are designed to get some support from the window pane above, but in this case we don't want to put any load on the plexiglass. Install L shaped brackets or an AC support bar to help support the AC unit from below the window.   Step 3
Step 4:  Test fit the AC unit in the window opening and measure the gap above the unit to the top of the window.
Step 5:  Score the plexiglass. Mark the plexiglass according to your measurements and then use a straight edge and scoring tool to make several passes over the plexiglass.   Step 5
Step 6:  Break the plexiglass. Position the scored line over a ledge and push down on the overhanging plexiglass to break.   Step 6
Step 7:  Line the window frame with foam weatherstripping and install the plexiglass.
Step 8:  Install the AC unit into the window. You can permanently attach the AC unit to the bottom support using bolts or epoxy (in this case we used industrial velcro because we wanted to be able to remove the unit from the support in the future).   Step 8
Step 9:  Line any gaps above or below the AC unit with foam or weather stripping.
Step 10:  Enjoythe cool breeze!
Tips & Advice:   We used a Zenith 5,000 btu unit from the Home Depot and it is very quite. We also have a Kenmore 5,000 btu unit in another room and the Zenith is MUCH quieter.


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