How to Install a Window Air Conditioner

Installing a window air conditioner is an easy way to keep your cool.

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Introduction

With the summer temperatures on the rise, you may need to install that window air conditioner — it’s easier than you think.

Tools Required

• Scissors
• Screwdriver

Materials Required

• Appliance cord
• Foam weatherstrip
• Window Air Conditioner
• Wood block

Project step-by-step (5)

Step 1 - 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.

Step 2 - Blocking

• 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 2x4 works well for this, but every situation is different.

Step 3 - 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.

Step 4 - 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.

Step 5 - 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.