How to Install a Window Air Conditioner
Installing a window air conditioner is an easy way to keep your cool.
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An hour or less
$150 - $400
IntroductionWith the summer temperatures on the rise, you may need to install that window air conditioner — it’s easier than you think.
- Appliance cord
- Foam weatherstrip
- Window Air Conditioner
- Wood block
Project step-by-step (5)
What type of window do you have?
- First, look to see what type of window you have. Window air conditioners fit best in single- and double-hung windows that slide vertically.
- Casement windows that crank open and horizontal sliding windows don’t work as well for window air conditioners.
- If you have a storm window, you may need to remove the screen or slide open the lower window.
- When installing the window air conditioner, you want to make sure it’s sitting level in the window opening.
- You made need to add some blocks between the windowsill and the air conditioner near the front (and possibly toward the back) to assure that the unit is level. Typically, a 2×4 works well for this, but every situation is different.
- Before moving forward, you’ll want to seal around the window. Cut, peel and stick 1-1/4-in. x 1-1/4-in. foam weatherstrip to the windowsill, as well as on top of the air conditioner or to the bottom of the window.
Install the air conditioner
- Some window air conditioners are quite heavy — you may need a helper.
- With the window open, lift the air conditioning unit into the window opening until the wings are even with the window jamb, centering it in the opening.
- Lower the upper window down on top of the air conditioner, holding it in place.
- Expand the air conditioner wings to close the gap on each side.
- (Optional) If you don’t mind putting holes in your window, secure the wings to the window.
- If possible, plug your air conditioner into a designated 20 amp circuit.
- If you need to run an extension cord, it’s always a good idea to use a heavy-duty appliance cord.
Originally Published: July 07, 2022