Window AC Security: 7 Ways to Burglar Proof Your AC Unit


Looking for a way to secure your window ac unit? It’s your coolest friend (literally!) but it can get snatched easily from the window even by a not-so-clever burglar.

In this article you can read the best tips on how to secure a window air conditioner while saving time and money in the process. The top three security measures you can take are:

1. Use an Air Conditioner Cage (Window Guard)

Cages are the most secure option because they don’t even allow the thief to reach the air conditioner from outside. They’d have to remove the cage first, but that would take a lot of time, energy and noise.

On top of providing extra security against theft, an AC unit cage will prevent it from falling on someone’s head in case it dismounts from the wall for some reason.

Think of situations like terrible hurricanes or a crumbling wall that can no longer support the unit, or simply poor installation. This terrible result can be prevented by covering the unit with a metal cage.

There are two different types of AC unit cages: First can be used for on-ground AC units and the second for window AC units. These are also called window guards. They are usually different both in size and setup so you have to make sure that you get the right type for your air conditioner.

Here is a solid window guard from Amazon. It’s adjustable so it’s dimensions are 30-40 x 18 x 18 inches. So make sure that it’s big enough for your unit before buying.

There’s also a good looking AC window guard from Home Depot. It’s dimensions are 40 x 18 x 18 and it’s more affordable, just under $260.

2. Use a Special Window Lock

Your AC unit can get snatched from outside if the thief climbs a ladder to reach it. The thief could also open or smash the window to snatch the air conditioner.

To protect the window that has your AC unit installed from opening, you can install the AC Security Window Lock Wedge (link to Amazon).

It’s designed exactly for this purpose and is fully adjustable, from 7-1/2″ to 14″ in length. So it can work with any standard window and any brand of air conditioner.

How does it make the window more secure? Basically it won’t allow anyone to simply push the window open, slide out the AC and sneak into the house. It definitely won’t allow them to steal the unit since it wedges the window down.

Sure, the thief could still smash the window open, but any smart thief will try not to make that much noise. And to prevent even that from happening, you can cover the glass panes with security window film which makes it much harder to break the glass.

This EZ-AC lock is 100% USA made and is made to fit US air conditioner window requirements. It’s simple to install and provides more security than makeshift wedges or the bracket that usually comes along with the AC unit, which also requires you to drill holes in the window frame.

Don’t get me wrong, the bracket is helpful for easier installation of the unit. But it doesn’t do much to address these burglary-related issues.

You could also use a regular adjustable security bar to secure the window from the inside. It can be used to prevent the intruder from opening the window on which the unit is located, or any other window for that matter.

3. Air Conditioner Support Bracket

A good support bracket can be used to secure a window AC and reduce the load on the window to prevent damages to your home and woodwork. It will also act as a deterrent against thieves because dismounting the AC from a support bracket is more difficult.

Option #1: AC Support Bracket

You should think about the size and weight of your AC unit and the size of the window to make sure that it fits well. For most units and especially larger ones, the best option in my opinion and that of many other home improvement geeks is the AC Support Bracket from Amazon.

I love this option because it doesn’t require any drilling. It fits windows with a minimum width opening of 23″ and a maximum width opening of 38 1/2″. It can also support up to 150 lbs. However, you should also know that:

  • it is not designed to work with side-to-side opening windows
  • it doesn’t work with homes other than 2×4 or 2×6 construction
  • doesn’t work with Frigidaire Gallery series air conditioners
  • probably won’t work if you have a stone ledge or any obstruction on the exterior of your home if it could get in the way of the supporting leg

The good thing is that it works with brick or concrete homes, as long as the above-mentioned obstacles don’t stand in your way. And the best way to use this support bracket is with standard or double-hung windows (of any material).

If your air conditioner doesn’t have flat bottoms, this bracket will still work well. But there may be a small gap between the unit and the bracket. This gap won’t affect the security or functionality, but it can easily be filled with foam insulation weather stripping if you want to.

Option #2: A/C Universal Heavy Duty Bracket + Free AC Security Lock (!)

This is another affordable and heavy duty support bracket that also features an AC security lock designed for better protection and stability.

How does it work? It transfers the weight of the AC unit from the window sash and sill to the support and window frame, which improves safety.

The bracket is only about 6 to 8 inches wide, so it will fit any window wider than that. It fits wall thickness from 4 to 11 inches and can support up to 160 lbs.

All in all it’s very similar to EZ-AC but it can also support slightly heavier units, since the maximum weight for EZ-AC is 150 lbs and for this bracket it’s 160 lbs. Just like the EZ-AC, this bracket also doesn’t require any drilling of outside wall or siding.

Keep in mind though that in both cases the AC is not secured to the bracket with bolts. You could drill holes to secure it with bolts to the support. Or instead, secure the AC to the window.

Perhaps the best part of the package is the security lock which is an extra product that joins the AC to the window sill. It acts as an additional burglar deterrent and for improved AC stability.

4. Install Flaps

A window air conditioner typically needs to be smaller than the window in order to fit properly. But there’s always some space left surrounding the unit which can make it easier to remove and can increase break-in risks.

You can screw in metal or plastic vent flaps over these gaps to secure the window better. Make sure that the flaps are pulled tightly to cover up the space. Use three or more screws to attach them directly to the window frame.

5. Get a window alarm

There are many window alarm systems that are easy to use, effective and very affordable. My favorite is the Doberman Door/Window Alarm that has an adhesive backside.

So all you need to do is stick it on the window and use the on/off switch to turn it on. If someone tries to break in through the window or dismount the AC unit, it will produce 110 dB of noise.

Considering the fact that it costs less than $10 and runs on cheap cell batteries you can’t get a better deal than that. There are more expensive and complicated alarm systems but I don’t think they’re necessary for this purpose.

6. Install a home security camera

You can observe the window area with a security camera. My recommendation is to get an affordable camera like Zmodo Wireless Cam which has night vision and motion sensor technology. When the motion sensor picks up on any excessive movement it will send you an alert on your electronic device so you can act quickly.

This is the best way to secure an entrance point or appliances/vehicles that are located outdoors, such as a window AC unit in this case when you’re not at home, since you can receive the alert anywhere if you have a WiFi connection.

7. Make the window difficult to approach

If the AC unit you’re trying to secure is not installed on a ground-floor window but one that is higher, make sure that no ladders are left nearby that the thief could use to climb up.

You can also make it harder to climb up by planting large vegetation under the window, especially thorny shrubbery. Thorny shrubbery can make it more difficult to approach a ground floor window or a basement window as well.

About Window Air Conditioner Security

Securing a window AC unit involves three simple methods. First option is to use an AC window guard/cage so that the unit can’t be reached unless the cage is dismantled.

Second option is to ensure that the window can’t be opened or smashed easily from outside. Using a good security bar can easily solve this problem.

Third option is to use a good support bracket. Additionally bolting the AC to the bracket will provide even better security. But in that case make sure that you don’t damage the AC.

If you apply at least 2 of these methods you can rest assured that thieves will not be interested in stealing your window air conditioner. Why should they, when there’s probably hundreds of other AC units in the neighborhood that aren’t secured in any way whatsoever? So I hope this information helps and that you’ll use it to your advantage!

Peter Boné

Chief editor of Security Latest with 5 years of real security work experience. I'm also a family man with wife and two sons. When I'm not turning homes into fortresses, the Boné family is usually on the Nintendo or on California's best hiking trails.

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