How to Keep Your Parked Car From Sweltering, and Get It Cool Fast

Wes Schwengels
May 22, 2018

Summer is almost here, which means it’s driving season. But while you’re frolicking on the beach, seeing the sights on vacation or even just catching a movie, your car is sitting there in the sun, baking. 

The temperature inside a car left sitting in the sun for one hour rises more than 40 degrees Fahrenheit, on average, studies have shown. So, if it’s 95 outside when you duck into a restaurant for lunch, your car can be hotter than 135 degrees by the time you’re done. We’re sweating just thinking about it.

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Image Courtesy of Pixabay

Before we go any further, a quick reminder: Never leave children or pets in a parked car, even for a few minutes, even with the windows cracked. Your child or animal can die quickly in these temperatures, and in some places, you can be charged with a crime even if they don’t.

There are ways to keep your car from feeling like an oven. And once you’re back in the car, you’ll want to get it cooled off as quickly as possible. But does that mean just cracking the windows and then cranking the air conditioner at full blast?

Let’s start with some ideas for keeping your car cooler when you’re not in it this summer.

1. Shade is your friend

One easy way to keep the sun from scorching your car is to avoid parking in it. This might mean taking a spot a little farther away from the store entrance in order to get under a tree, but a few extra steps will be worth it in an hour’s time. 

If there’s a nearby parking garage that you can use instead, that might be worth it, as well. Many of them are free, but even having to shell out a couple bucks might be worth it if you’re in the midst of a heat wave.

2. Get a windshield sun shade

Popping a screen into place each time you park in the sun will help keep your car from reaching record highs. Many of these devices also have reflective or heat-absorbing materials to help cut the amount of ultraviolet rays entering your car. 

Make sure you get one that’s the right size for your vehicle — SUVs have more surface area to cover than subcompacts, obviously. And while you’re at it, look into screens for the side or rear windows, as well. They might take a little more time to install, but if you’re going to be leaving your car for an extended amount of time, it’ll be worth it.

3. Buy a solar-powered fan

If the sun’s providing all this energy, you might as well put it to work. On a sunny day, a solar-powered fan can drop your car’s interior temperature by about 15 degrees — it won’t replace your air conditioner, but it will definitely help.

These fans hang on the top edge of your car window, so you’ll have to leave at least one of them cranked down a little bit (more on that later). They then blow some of the extremely hot air out of your car and replace it with cooler air from outside. 

Since it relies on the sun to work, you’ll need to put your fan on the side that’s getting the most direct rays. Also, be aware that it won’t work as well if it’s cloudy but still hot. 

4. Keep your windows open a crack

Even if you don’t have a solar-powered fan, leaving your windows down just a little bit can provide some ventilation — please let there be a breeze! — while your engine is off. Again, you won’t confuse your car’s interior for the arctic tundra, but every little bit helps.

A couple tips for leaving your windows down: Don’t leave so much space that an opportunistic thief could reach an arm in and unlock the door or snag some valuables. And don’t leave them down if you’re expecting a dust storm or summer monsoon. The cleanup or water damage won’t be worth it.

5. Cover your steering wheel, seats and other surfaces

No matter how hot it is, you have to touch some parts of your car’s interior at some point. So, keeping things like your steering wheel, gear shifter and seats covered can save you some pain. 

Get a dash cover to help protect the vinyl or plastic from being damaged by the sun’s UV rays, and from absorbing so much heat. Buy a steering wheel cover, or throw a towel over the wheel and the gear shift knob. Invest in seat covers or at least throw a beach towel or blanket over the parts you’ll have to touch — especially if you’re wearing shorts. Ouch.

While we’re at it, make sure to clean your dash and seats regularly, too. You can add protectants to the vinyl on the dash or your leather seats to prevent cracking, fading and other wear. Your car will look better — and be worth more — if it doesn’t look like it’s been beaten up by the sun.

Get your car cooled down faster

When you do have to get back in the car, you’ll want to cool it off as fast as possible. Step 1? Don’t immediately start it and crank the AC. Instead, if you can, let the doors stand open for 15 to 30 seconds to give that superheated air a chance to escape. 

To get your car cooled down faster once you’re moving, try these tips:

  • Don’t start the air conditioning until you’re moving. Running the AC at idle won’t do you as much good, and will waste fuel.
  • After you start moving, roll the windows down and turn the AC on full blast on fresh air mode (not recirculating). Have the air blow into the footwells as well to move the hot air out of there.
  • Once the AC has cooled down, roll up the windows and set the temperature no colder than you need it. Cranking it on high all the time will waste gas. And put it on recirculating mode once the air in the cabin has cooled off.

Of course, in order for this to work, you’ll need your air conditioner to be in good shape. That means your AC compressor is healthy and your refrigerant is staying where it’s supposed to. If your AC is acting up, check out the possible causes here and have your mechanic take a look as soon as you can. 

Make sure your engine is cool, too

While we’re at it, it’s important to make sure your car’s cooling system is in in working order, as well. Check on your coolant level at least once a month to ensure you’re not in danger of overheating. And take a look at your radiator hoses. If they look cracked or worn, it’s time for new ones.

If your engine gets too hot, it can suffer severe damage, leaving you stranded on the side of the road — in the sun — and facing expensive repairs. That’s one quick way to ruin a vacation.

Wes Schwengels

About the Author

Wesley has been editing a wide range of content for nearly two decades, gaining a depth of knowledge about automotive maintenance and ownership.

1 User Comment

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By , July 28, 2017
Hot cars are one of my least favorite things, definitely going to try some of these solutions out!