How to Install a Window AC Unit

When summer’s imminent, you’ll look for methods to stay cool during those hot months. And with weather forecasts saying summer 2022 will be hotter than average, installing a working air-con in your space is important.

One type of air conditioner you may want to install is a window AC unit. A window AC is an excellent alternative if you’re searching for a traditional and cost-effective means of cooling down a room. It’s a safe bet that can effectively cool spaces of varying dimensions.

Recent models are more energy-efficient and produce less AC noise than ones made decades ago. Additionally, this guide will address any questions you have about installing window AC yourself. Everything you need to know about setting up a Window AC unit is covered here.

We’ll provide tips on installing a window air conditioner and things to consider before making the installation.

Let’s go!
Factors to Consider Before You Install a Window AC Unit

A window air conditioner is the most convenient and cost-effective cooling method. These portable air conditioners have improved dramatically in efficiency over the past decade, and they can effectively cool rooms of almost any size. In addition, they’re also very simple to set up.

Before diving into installation procedures, let’s take you through things to consider before installing a window AC unit.
Room Dimensions

Regarding air conditioning, room size matters; a big unit will easily remove enough moisture from the air. Meanwhile, a small unit won’t be able to cool the room adequately on hot summer days.

A window air conditioner’s cooling capability is in British Thermal Units, so you may use that number to determine the best size for your space (BTUs). A common range for window air conditioners is between 5,000 and 25,000 BTUs. Twenty British thermal units (BTUs) are requirements for every square foot of space.

So, start by taking some measurements of the space you intend to cool. Then, take the room’s dimensions into account using the following formula: Area = Width x Depth

You can determine the area of a rectangular, L-shaped, T-shaped room by taking the sum of its shortest length and breadth. You’ll get the central region that way. Then, measure the length and width of each section of your room and multiply the results to get the total area.
Are you Getting the Best Product?

Here’s some good news if you’ve been shopping for a new window air conditioner: we’ve got some options for you.


Air Serenity Series Quiet Window Air Conditioner, Quietest (6,000 BTU)

Price: $394.69 – $530

This Haier window air conditioner is one of the quietest and most efficient models available.


Smart Room Air Conditioner (8,000 BTU) GE price: $330.00 – $430

With GE Appliances’ first-to-market voice-enabled air conditioners, you can set the temperature and turn the unit on and off without even getting out of bed.



Price: $289.00 – $390

This high-performance 8,000 BTU LG window air conditioner is perfect for areas up to 17 by 20 feet and is excellent for cooling large spaces quickly.


Smart Window A/C (10,000 BTU) FRIGIDAIRE

Price: $399.99 – $600

This Frigidaire, which has earned the Energy Star label, is one of the most aesthetically pleasing window air conditioners you’ll find around.
Inspect Your Window

Air conditioners mounted in windows typically fit into double-hung windows. But they can also be installed in other types of windows that open outward, such as sliding or casement windows. (Before attempting any sort of installation, be sure to consult the air conditioner’s manual.)

Double-hung windows are the most common types; therefore, we’ll be telling you how to install a window AC unit in them.

When looking for an air conditioner, having the window measurements handy can help you find one that fits snugly in the window. Importantly, ensure you lift the lower sash before taking any measurements.

Also, consider fire safety when determining where to put the air conditioner. For example, you can’t install your window AC in an egress window that should be an escape route in the event of a fire.
Think About Saving Energy

An air conditioner’s Energy Efficiency Rating, or EER, indicates how efficiently it cools a space. By dividing the unit’s BTU rating by watts, we may determine its EER. An example is an air conditioner with 12,000 BTU capacity and 1,200 watts of power consumption with an EER of 10.

Don’t get Seasonal Energy Efficiency Ratio (SEER) mixed up with Energy Efficiency Ratio (EER). The former measures the efficiency of central air conditioners,

Standard window air conditioners have EER ratings between 8 and 12. To save energy and money, you should aim for a rating of 10 or better. In addition, check for energy-saving features like digital temperature controls, adjustable fan speeds, and sleep modes.

Related Article: How Much Does AC Installation Cost?

saving energy
Preparing Your Window Before AC installation

Please read the following instructions carefully to prepare to install a window AC unit seamlessly:

  1. Inspect and Clean Your Windows First

It is essential to check the window’s condition carefully to ensure it will function properly. Inspect the area around the window frame for decay or other dents.

Focusing on fixing what’s broken should be your top priority. You definitely don’t want to discover an issue with the window after installing your appliance.

You may never get to clean the window until the hot season is over. Therefore, you should clean it thoroughly before you install a window AC unit.

  1. Take Away Anything That’s Blocking The Window

It’s time to clear out the window sill of any ornaments or plants that may be there. Removing obstacles from the space is important when setting up a window AC unit.

Similarly, you may have a storm window frame installation. In such an instance, you’ll need to take it down because it may get in the way of the overhanging section of the a/c.

  1. Make Sure The Circuit’s Load Isn’t Too High

Before installing a window AC unit, ensure the circuit can handle the load. If your window air conditioner is on a dedicated circuit, ensure the circuit is powerful enough.
Step By Step Guide To Installing a Window AC Unit

Before we dive into how to install a window AC unit, let’s see the necessary tools for installation:

Torx screwdriver
Screws and brackets supplied by the manufacturer
Measuring Tape

Let’s get into the complete guide to installing a window AC unit.

  1. First Unpack Your Air Conditioner and Locate The Middle of Your Window

AC installation experts advise that you exercise caution when removing your new AC from its packaging. This precaution is because the unit’s backside can have sharp edges.

Furthermore, to ensure you received all the necessary components, open the package and remove everything. Then, take a tape measure to your window and make a pencil mark in the middle. In addition to making installation simpler, marking the position will ensure that the side panels reach the same distance on either side of the window.

  1. Open Your Window and Get It Ready For Use

Open up your window, and install the manufacturer-supplied weather strip at this point. These strips not only shield your windows from potential harm during AC installation or removal. But they also prevent needless air by sealing any gaps that may be present.

A weather strip isn’t necessary for your air conditioner to function, and they aren’t standard equipment on all models. In other words, you can do without one.

  1. Attach Sides Panels

At this point in your window AC installation process, you may slide the panels into position on your unit. Screw the movable panels into your window air conditioner after sliding them all the way.

Fill in holes with screws to keep out warm air, pollutants, and allergies.

  1. Stick Your Air Conditioner in the Window

Lift the air conditioner and place it in the middle of the window. The glass on top of the air conditioner should have a convenient sliding position to ensure a snug fit.

Remember that the unit’s bulk is on the outside, and exercise caution when you move it. With the window closed, the air conditioner should be safe and sound.

Pro Tip: You’ll want to have two individuals do this. It’s best to have a helping hand, even if you’re strong enough to move the window and AC unit yourself.

  1. Mount the L-Brackets

You’ve made it through the most challenging portion. At this point, all that remains is to lock everything down and put the finishing touches. In this step, the installation process can vary according to the manufacturer, although most windows come with at least one L bracket.

To fully install a window AC, simply screw an L-bracket or multiple L-brackets at the top of the uncovered window. Of course, the primary worry after installing window AC units is that the AC will push up the window. But this L bracket will ensure it stays tight.

If your air conditioner doesn’t have a bracket for holding the window in place, you should probably get one locally.

  1. Fasten/Attach Panels

If you have it, putting window padding on the sides of an open window is a good idea. First, just extend the side panels to cover the opening to compensate for the lack of window cushioning. Afterwards, you should use the manufacturer-supplied screws to secure both side panels to the window.

  1. Lock it Down And Turn On The Air Conditioning

Some air conditioners easily attach to the inside of a window sill. And this happens with the help of brackets and screws provided by the manufacturer.

Some manufacturers may not see the need for this added layer of protection. But screw them in now if you have them. And that’s it with installing a window AC unit.

Don’t forget to turn on the air conditioner after plugging it in. Your room should feel noticeably cooler almost instantly.

installing a window ac unit
Dos and Don’ts Of Window Air Conditioner Installation

We have provided the best way to install a window AC unit. But the question of how to install a window air conditioner naturally raises the related query of whether or not the process is vital. And this position is a common one among the rising percentage of window air conditioner owners in Canada.

While installing a window air conditioner, there are a few extra tips you should keep in mind beyond the detailed guide in the earlier section. These tips include critical Dos and Don’ts of window AC unit installation.
DOs of Window AC Installation

The following are things you should do when installing window AC yourself:
Assemble Supporting Panels And Rails

Using screws, secure the bottom and top mounting rails to the wall above and below the window. This fitting will keep the unit from falling out. Then, slide the side panels along the grooves on either side of the unit and secure them in place. Finally, fill the spaces between the window AC and the window frame with panels.
Ensure L-Brackets Installation

In most cases, you can install a window AC unit without additional bracing. But a particularly heavy or bulky unit may need support in attachment to the wall (usually above 100 pounds). You could use L brackets for these reinforcement purposes.

In pairs, the L-shaped brackets provide a firm foundation for the whole setup. In addition, these brackets help remove the strain off the window sill after installing an air conditioner.

The L brackets not only protect the unit from falling out of the window. But they also keep the window from opening and inflicting damage. In addition, the newest models available on the market are installable without drilling.
Foam Seals Should Be Put In Place

In trying to keep draughts at bay, it’s necessary to seal the space between the window glass. The unit will have to work harder to maintain the desired temperature and humidity levels, and it will be unable to prevent the buildup of moisture and dust if there’s any form of air leakage.

A foam seal, typically included with the window unit, can function well as a gap filler.
It’s Important To Keep The Tilt In Mind

You should tilt your window air conditioner so that condensation collects in the drain pan instead of dropping into your room/space. Again, refer to the manual for the correct inclination, but remember that it should be no more than half an inch.

Meanwhile, the manufacturer may already fit the drip pan at an angle on specific modern AC models. This addition eliminates the need to tilt your window AC unit upon installation.
Don’t forget to Leave Enough Room For Ventilation

Check that nothing is closer than 20 inches to the air conditioner, including tall vases, walls, or furniture. Suffocating your window air conditioner will prevent it from functioning correctly.
DON’Ts of Window AC Installation

You should avoid the following when you look to install a windows AC unit:
Not Having a Professional Do the Installation for You

An air conditioner window unit can weigh anywhere from 50 to 100 pounds, making DIY installation dangerous.

Putting in the screws to hold it in place can be complicated, even if you can carry it. That’s why a two-person installation crew is the recommendation of experts.
Forgetting To Fasten the Side Panels In Place

The side panels must be secure and tight, so the air conditioner can’t fall out of the window. To do so, just drill holes in the side panels and insert the screws provided with your air conditioning unit.
Not Verifying Your Measurements

Your air conditioner must be a snug fit in the window; therefore, measuring is necessary. Take careful measurement of the window’s width and height. And take the room’s dimensions with you when you shop for an air conditioner.

The air conditioner’s area that can be cooled or heated is usually in writing on the box it comes in.
Plugging Your Window Air Conditioner into an Extension Cord

To avoid potential electrical hazards, you should never consider plugging your window AC into an extension.

Always have an electrical outlet within reach when setting up a window air conditioner. Don’t use extension cords because they pose a fire hazard and could make your air conditioner’s warranty null and invalid.

Related Article: AC buying Tips: How To Find The Best AC For Your Home

plugging window air conditioner
Use The Air-Con Experts

After going through this guide to installing a window AC unit, you can likely do it independently. But that doesn’t remove the fact that you may still encounter complications.

In fact, you may not even want to undertake DIY methods. That’s why we’re here for you with top-notch AC installation services.

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