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How to Install a Window Air Conditioner: A Step by Step Guide

Summer is upon us, and you know what that means: air conditioning.  It’s the top priority for homeowners across the nation suffering from the sweltering heat. For those who don’t have the privilege of central air then installing a window air conditioner becomes a means of survival.

window air conditioner installation

Not every air conditioner unit will fit in every window unit type, which is something to consider early on before you begin to install.  Before you do anything, read about the style of unit you’re purchasing and what type of windows your home has.

Most units are designed to fit into a double-hung window style, where the lower sash will lower and raise accordingly.  Take measurements before making your purchase and installing to ensure that your new unit will fit in your window.

Choose Your Window

Your first step is deciding what window you’re going to be placing your air conditioning unit into.  It is a matter of personal preference: the bedroom, the family room, or the kitchen.  The outlet you’ll use should be three-prong, but if there isn’t a three-pronged outlet close enough to reach the window, you don’t have to alter your plans just yet.

Although, you may want to consider the weather conditions that are typical for the window you select, for example, does rain tend to hit that side of the house more than the others?  Does that window face west and will eventually force the unit to work harder due to sun exposure?  These are things you may want to consider when making your window selection.

Plan to use an extension cord to connect the air conditioning unit to the nearest three-pronged outlet, but be sure that this outlet isn’t already overloaded with other devices.  If you tend to run a hairdryer or other heavy-duty electronic devices on this outlet, pick another one because you’re going to overload the circuit or blow a fuse.

Clean and Prepare Your Window

You won’t be removing your unit for a good while, so make sure you wash the glass of your selected window inside and out.  Prepare the window to install by clearing the area around it, removing tripping hazards and obstructions, and taking out the storm window frames and screens.

clean window

The Window Air Conditioner Installation Process

Step 1

You’ll also be following the manufacturer’s instructions, but begin by placing the air conditioning unit inside the window (you may need to recruit a friend to help lift the unit into the window for this part).

The bottom sash of the window will be lifted up for an optimal opening, and you’ll be keeping the unit balanced as you slide the bottom flange against the outside edge of the windowsill.  Then, you’ll lower the window sash against the top of the unit, securing it against the topmost flange.

Step 2

To prevent the sash from being raised, you’ll install two screws through the upper flange on the air conditioner case into the window sash.  This will prevent the unit from falling or slipping out of place.

Be sure to drill pilot holes first or you could split the wood on the sash.  Then, attach the L clips that attach the bottom sash to the top sash frame.  Additionally, you can cut spacers, wedging them between the bottom and top sash of the window frame.

Step 3

Now, it’s time to pull the side curtains out to protect the interior of your home against exterior elements like bugs, rain, hot air, and moisture.  You’ll be screwing or clipping these side curtains into place.

The side curtains will also help seal the room to keep the unit productive in churning out cold air and stabilizing a cool temperature.  Some people opt to cut white foam insulation board to fit around the outside opening of the unit to protect it against the sun and to keep the unit from overworking should it be on the side of the house that is exposed to lots of UV light.

Step 4

Seal the gap between the frame of the lower sash and window on the upper sash with the foam that your unit provides you.  The foam filler can easily be cut to the appropriate length and slipped into place.

If for whatever reason your air conditioning unit didn’t come with a foam seal or you’ve lost it, you can purchase foam strips separately at a hardware store and fashion it yourself.

Step 5

All that’s left is for you to plug in your new unit and enjoy the cool air.  Congratulations, you’re a pro!

All Units Aren’t Created Equal

The most important thing to remember with air conditioners is that all units are made differently, so when taking on the installation yourself, be sure to follow the manufacturer’s instructions letter by letter.

Aside from drilling and screwing, there’s no demand for highly experienced skills for installing an air conditioning unit.  Anyone can do it, and like anything else, it just takes a little time.  The reward, though, is really cool.

Choose Feldco for Installing Your Windows

You don’t want to be placing your window air conditioner in any old window. If you’re dealing with drafty windows, even with the most energy efficient air conditioner, you’ll be losing money over the long term.

If you’re looking to capitalize on having the best possible window air conditioner setup in your home, get professional window replacement with Feldco to make sure your windows are perfect from the start. Get a free quote today.

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