Can You Use a Window AC Unit While It’s Raining?

There are times when even though it’s raining outside, it’s still sweltering inside — and having your window AC turned on is essential. But is it ok to run an AC unit while it’s raining?

Everyday rain won’t damage your window AC unit since the unit is made to be waterproof. The only thing that isn’t safe for a window AC when it’s raining is the debris that strong winds can carry. That said, it’s best not to use your window AC during thunderstorms in case of a power surge.

Now that you know that you can use your window AC during the rainy season, there are still some precautions to keep in mind to stay safe. Let’s take a look at all you need to know.

Can Rain Damage Your Outdoor Window AC Unit?

Window air conditioning unit on a cabin

Your window AC unit won’t be easily damaged by rain, even though it’s got lots of potentially vulnerable electrical parts. Luckily, manufacturers ensure that those electrical parts are sealed well. 

The only thing that could harm your window AC is standing water. If, for some reason, floodwaters reach your window AC, or if the AC unit has been soaked in a downpour, this can cause damage. In these cases, there’s a high risk that the water has managed to get into the sealed part of the electrical system. 

Nonetheless, everyday rain will not damage your Window AC.

What Happens if Your Window AC Unit Gets Wet? 

Technically, your AC produces water vapors from air condensation to produce cool air. In that sense, the unit gets wet regularly — but not to the point that it gets incredibly soaked with water. 

As we mentioned above, your unit is waterproof, and everyday rainy weather won’t be an issue.

But for peace of mind, we can always take precautionary measures to prevent damage to the AC unit. Let’s break down how rain can affect the AC unit.

The Window AC Unit Can Withstand Weather Patterns

The rain won’t have any impact at all on the AC unit. HVAC manufacturers ensure that the electrical system inside is well-sealed.

They wrap up the wiring inside with waterproof materials to ensure that droplets of water can’t get inside. 

In addition, HVAC manufacturers test how their waterproofing materials work on each unit.

Using the AC Unit With Standing Water May Cause Damage

The only real risks to your AC unit are flooding and debris. If your unit is submerged in water due to a flood, it’s probably not going to work again. Never attempt to use an appliance that has been soaked with water.

Storm Debris Can Damage a Window AC Unit 

During the rainy season, there are times when the wind is very strong. Typically, it carries some leaves or twigs that might get inside the Window AC. If these are not removed, it can cause mild molds to build up inside the AC, which is not suitable for the unit’s health.

In addition, those twigs and leaves will be attractive to insects like ants. They might end up building their homes inside the unit. Or worse, they might end up eating up the electrical parts inside. A regular check-up after every rain or storm is necessary to avoid this.

AC Coverings Protect the Window AC Unit

This is one of the reasons why it is advisable to buy an AC unit cover (on Amazon). It will protect the AC from any debris. Before purchasing an AC covering, you should check the dimensions of your AC to get the right fit.

Although some homeowners attempt to cover the AC with home remedies like a plastic bag, DIY coverings can trap the hot air that is supposed to be released from the AC. If the air can’t escape properly, it might pose electrical damage to the AC. The heat might melt the electrical wires inside.

Can You Run a Window AC Unit During a Thunderstorm?


It’s not advisable to use your window AC unit during a thunderstorm. This isn’t because the lightning might strike your appliance and cause a fire, as you might be thinking. It’s because a power surge could happen.

Power Surge

In the case of a power surge, any appliances plugged or operating might experience an electrical meltdown. Due to the power surge, the electrical parts inside will melt or burn due to the sudden jolt of electricity.

Even if this doesn’t result in fire, the window AC will possibly be unusable. Repairing it could be very costly, and the technician might suggest you buy a new one instead.

To prevent this from happening, it’s recommended to unplug all appliances, especially the window AC unit, during a thunderstorm. You can use it again once the thunderstorm passes.