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Many parts of the country are seeing extreme heat in the coming weeks. So, it’s important that you know how to most effectively use your car’s air conditioner. However, with gas prices still floating around record-high numbers, it’s a tough dance to keep cool and keep fuel use efficient. Here are some tips to keep yourself cool without wasting your gas.

Just get in and drive!

2022 Nissan Maxima driving at speed on a two lane highway in the desert.
2022 Nissan Maxima | Nissan USA

NBC Washington recently teamed up with Mike Quincy of Consumer Reports to give some tips on rapidly cooling your car on these hot summer days. First and foremost, you should just hop in your vehicle and start driving.

While it may be tempting to use your remote start and let the car run and get the air conditioning flowing before making your way out to the car, it’s not a great idea. Your car’s AC compressor works more efficiently the faster your engine is spinning. So, sitting at idle is going to make it take its sweet time cooling down.

“Your car’s air conditioning works much better when you’re actually driving because the faster your engine turns, the faster the AC compressor runs, which lets the system cool more effectively,” says Quincy.

Turn the AC down as low as possible and open the windows

the climate controls found in a new tesla model s, manage your climate to keep cool in your car
Tesla Model S Climate Controls | Tesla

Yes, it may seem counterintuitive to roll your windows down. However, according to CR, this is the quickest way to cool your car down.

Nobody likes to sit in a hot car with stagnate air and the fan blowing even more hot air out of the vents. So, roll all the windows down to get fresh air flowing through as the AC system begins cooling. Once the air coming out of the vents is nice and cool, roll the front windows up entirely and leave the rear windows cracked.

Leaving the rear windows cracked ensures that the fresh, cold air is pulled to the back of the vehicle, too. This is especially important if you have passengers in the rear seat.

Turn off the auto start/stop

2016 Volkswagen e-golf electric vehicle EV engine start button
Stop/start button | Braden Carlson, Motorbiscuit

Considering the auto start/stop system is there to save you fuel, this also may seem counterintuitive. However, it is part of the game that is balancing fuel savings and battling the heat.

The theory behind this step is that shutting off the engine when the car stops is also shutting down the AC compressor. Depending on your vehicle’s internal temperature, this could actually cause the vehicle to use the AC compressor less efficiently. Stopping and restarting the compressor gives the vehicle’s interior the opportunity to heat back up when the engine is off, thus giving the AC more work to do once the engine starts again.

Of course, using the car’s recirculation system also helps in this scenario, as many modern vehicles disable the compressor once the desired internal temperature is reached if the recirculation mode is on.

However, CR also recommends shutting off the recirculation feature if you have passengers in the back seat that do not have dedicated vents. This could cause the rear-seat air to heat up. Letting your passengers keep cool in your car is important, too!

It’s a difficult dance to stay cool and keep money away from the gas pumps

Gas pump at a gas station.
Gas pump | Getty Images

Air Conditioning Expertise: How to Get the Most from Your Car’s AC

Ultimately, applying these tactics work in theory. However, your mileage may vary. No pun intended.

The best way to find out what works best for your fuel economy is to give these tips a try and see what your vehicle works best. Best of luck, and stay cool out there this summer!