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How to Install a Window A/C Unit

Window A/C Unit

You’re preparing for the summer heat, and purchased a window A/C unit. Now you need to install it, but where do you start? Window A/C units are a great solution to help keep a room cool during the summer, mainly because they're easy to install and less costly then installing central air. Cool off this summer in as little as five steps!

1. Check the Window

Men checking window

Before you even start installing your A/C unit, double check the window. Make sure it's structurally sound and able to handle the weight of the unit. Don't install a unit in a window that is rotted out or damaged. Have an electrical outlet close by, and never connect a unit to an extension cord.

2. Prepare the Window

Measuring window

Install weather stripping (if it was provided by the manufacturer) around the opening of the window to ensure an air-tight seal. Find the center point of the window, and mark it.

3. Install Unit and Side Panels

Window A/C side panels

Slide the side panels into place and secure the panels with screws. Insert the window unit into the window and extend the accordion sides panels and screw them into place.

4. Finish Up the Installation

L brackets

If there are any gaps, use foam weather stripping to fill them. Most units come with an L bracket to hold the window in place. This will help prevent the window from opening up and the unit falling out.


5. Start Cooling

Window A/C Unit

Now that your unit is securely in place, go ahead and plug it in and set to your desired temperature. Tip: Never use an extension cord to power a window A/C. Check the air filter once a month when using and keep the filter clear of any obstructions.

Now that you’ve mastered installing a window A/C unit sit back, relax, and enjoy that wonderful cool air your new unit will provide! For more unit-specific information, contact the manufacturer or visit your local Do it Best store.

While do-it-yourself projects can be fun and fulfilling, there is always a potential for personal injury or property damage. We strongly suggest that any project beyond your abilities be left to licensed professionals such as electricians, plumbers, and carpenters. Any action you take upon the information on this website is strictly at your own risk, and we assume no responsibility or liability for the contents of this article.


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