Can You Run Your AC During a Thunderstorm?

The summer months bring scorching weather full of sweaty, muggy days that send you straight into your air-conditioned home. But when there’s a thunderstorm rolling in, you might find yourself asking, “Is it OK to run your AC during a thunderstorm?” 

We’re here to tell you to proceed with caution if there’s a storm brewing. Running your air conditioner during a thunderstorm can lead to a damaged unit, so it’s best to turn it off when the dark clouds begin to roll in. Fortunately, the humidity and temperature decrease when it rains, so you’ll still have some relief without your air conditioner.    

Why Running an AC During a Thunderstorm Is Bad

The main reason to cut the AC during a thunderstorm is potential lightning strikes. Although it’s rare, lightning can hit your home. There’s a point on your house, known as the electrical drop, where utility lines and house connect. It’s a vulnerable point, and if lightning strikes, it could cause a power surge inside your home. 

If any part of your HVAC system is running when that happens, there could be extensive damage. 

AC Damage Caused by Lightning Strikes 

Extreme heat courses through your HVAC system after a lightning strike. The plug and other internal electrical components can melt, rendering the unit inoperable. At this point, you will need to call a professional technician to repair or replace the entire system.  

Even if the unit turns on after a lightning strike, the controls may still be damaged. The good news is that the chances of a fire or explosion are low because your AC unit is sufficiently insulated.  

Lightning Striking Window Units

Window units and ductless mini-split systems are also at risk for lightning strikes. The risk increases on higher-level apartment buildings. Because window unit lightning strikes are rare, it’s generally safe to leave your window unit plugged in but not running. 

Like an HVAC system, if your window unit takes a lightning strike, the plug or power port could melt or the circuit panel could be damaged. Such damage also needs to be repaired by a professional technician. Depending on the extent of the damage, it might be more sensible to replace the entire unit.  

Take Action to Protect Your Air Conditioner 

Is it OK to run your AC during a thunderstorm if you have a surge protector? Most HVAC specialists will tell you this doesn’t work as well as you’d hope.  

Surge protectors don’t provide enough protection against a lightning strike. If you live in an area prone to electrical storms, there are some valuable tools for protecting your air conditioner. You can use lightning rods, conductors, and ground rods to create an alternative path for the lightning. 

Instead of coming toward your home, it will hit the ground and leave your electrical system untouched. There’s no guarantee your home won’t experience a power surge, so it’s still a good idea to leave your air conditioner off during a thunderstorm.  

Can I Run My AC During a Rainstorm? 

Is it safe to run your AC when it’s just raining? Outdoor units are designed to operate efficiently during rainstorms with no risk of damage, with one exception. In heavy rainfall and potential flooding, be cautious of standing water near the outdoor unit. 

Shut it off immediately using the switch on the electrical panel if water begins to collect. Even after the water dissipates, don’t immediately use the air conditioner. Instead, contact a trusted professional technician for a complete inspection to verify there is no damage, and the unit is safe to use. 

Lightning Damage from Running an AC During a Thunderstorm 

Predicting a thunderstorm isn’t an exact science, so you can’t always avoid the potential damage they cause. In fact, you might not even be home when the storm hits, leaving your unit vulnerable. In that case, simply shut it off or unplug window units the first chance you get. 

If you suspect lightning damage once the storm ends, schedule an appointment with an HVAC technician to evaluate your equipment. Damage isn’t always noticeable, and they’ll know what to look for. You shouldn’t attempt to make any repairs yourself because of the dangers of electricity. 

Need Your AC Inspected After a Storm? 

If you’ve recently experienced heavy rains or thunderstorms, you’ll benefit from having your AC inspected to ensure it’s safe to run. Our team of trained professionals at Energy Pro Heating & Cooling is ready to step up and get the job done. Contact us today to schedule an appointment for your HVAC inspection. 

April 5th, 2022 | Heating and Cooling