How to Install a Window AC Unit

What type of window do you have?

• In order to know how to install window air conditioner properly, you first have to make sure you’ve got the right windows.
• Look to see what type of window you have. Window air conditioners fit best in single- and double-hung windows that slide vertically.

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• 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.

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Blocking

• When learning how to install 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.

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Weatherstrip

• 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.

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Install the air conditioner

• Some window air conditioners are quite heavy — you may need a helper. If the air conditioning unit needs to be cleaned, do it now before it is installed.
• 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.

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• 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. Find the coolest deals on the best window air conditioners before it gets too hot.

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• (Optional) If you don’t mind putting holes in your window, secure the wings to the window.

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Electrical Connection

• 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. Here are some simple steps to troubleshoot the issue if your window AC isn’t blowing cold air.

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