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Getting into a parked car on a sunny summer afternoon can literally feel like getting into an oven. Thanks to the greenhouse effect, the air inside a car can easily become 50 degrees hotter than the outside air – as if the outside temperature wasn’t already hot enough.

Overcoming temperatures hot enough to bake cookies can take some time, which means you’re left sweltering for several minutes as your A/C works to beat the heat.

Don’t worry, you don’t have to suffer for long. Read on and find out our simple procedure for how to cool down your car quickly for when you feel like you’re about to melt.

For short term relief, here are our main takeaways:

  • Roll down windows and open doors to get hot air out.
  • Turn on your A/C – but not to the max.
  • Ensure your A/C is running at peak efficiency.

How to cool a car down quickly

Getting hot air out of the car

One way to get hot air out of the car to simply roll down the windows for the first minute or so of driving. If you happen to have a sunroof, opening it is especially helpful, because hot air rises while cooler air sinks.

Another great way to get a head start before you even get in your car is to roll down the passenger-side window, then open and close the driver’s side door about five times. The door acts as a sort of pump, forcing air out the open passenger window. In one test, this tactic got rid of ⅔ the excess heat within a matter of seconds.

Remember, you’re starting out with a car interior that may be 50 degrees hotter than the outside air. So, if you can get rid of that super-hot air and replace it with regular outside air (which is merely hot), you’ve taken one big step towards cooling off the interior and given your A/C system a major assist.

Turn on your A/C – but not to max

Cool down your car quickly by turning on your A/C, but not all the way. When an automotive A/C is set to “max,” it takes air from inside the car’s passenger compartment, cools it, then blows it back into the car. Start by setting it to halfway until the car’s interior begins to cool.

The issue is that the air inside your car is hotter than the air outside. If it’s 100 degrees outside, it might be 150 degrees inside your car before you start the cooling process. So, if your target temperature is 70 degrees, an A/C set on “max” would have to cool the air down by 80 degrees.

If you turn the A/C on but not to “max,” it pulls air from outside the car. So instead of cooling the air down by 80 degrees, it will only cool it by 30 degrees – for example, from 100°F to 70°F. In other words, it’s going to cool your car down much more quickly.

Once the car interior starts to get cooler than the outside air - after you’ve rolled up the windows – that’s when you should set the air conditioner to “max” and recirculate that cooler air through the A/C system.

Next steps for a long-term solution

Make sure your A/C is running at peak efficiency

The better your car A/C works, the quicker it will cool you down. If all it does is blow lukewarm air on hot days, your car will never reach a comfortable temperature.

If your car’s air conditioner no longer does a good job cooling the air, it’s most likely low on refrigerant. It’s a common problem on cars that are at least a few years old, since the rubber A/C components can dry out over time and develop tiny leaks.

Luckily, you can fix this problem in about 10 minutes with a single can of A/C Pro®. It both recharges the system with refrigerant and seals the leak that caused the problem.

Thanks to its unique formula, A/C Pro® can actually help produce colder air than when the car was brand-new.

Note: If your A/C is already fully charged with refrigerant, trying to add A/C Pro® will not make it colder.


To recap, you can cool down your car quickly by following these handy tips we covered:

  • Roll down the windows for the first minute or so of your drive (or roll down one window and then open and close your door several times).
  • As soon as you start the car, turn the A/C to its coldest temperature setting, but do not set it on “max.”
  • Once you roll up the windows and the car interior gets cooler than the air outside, go ahead and switch the A/C to its “max” setting.
  • If your car A/C is blowing warm air because it’s low on refrigerant, recharge the system with A/C Pro®.