Most drivers use their car’s air conditioning inefficiently, wasting fuel and reducing cooling performance. Simple mistakes in how you operate your climate control can cost money and leave you uncomfortable in hot weather.
The right techniques can cool your car faster while using less energy, but they require understanding how AC systems actually work. Instead of just turning everything to maximum and hoping for the best, specific strategies work with your system’s design rather than against it.
Making small adjustments to your AC habits can have a significant impact on both cooling effectiveness and fuel consumption. Here’s how to get better cooling from your AC.
1. Skip the pre-cooling and start driving
(Image: © Shutterstock)
Your car’s AC system works much better when you’re actually driving because the faster the engine turns, the faster the AC compressor runs. Don’t waste time and fuel letting your car idle while trying to cool down.
Instead, start driving immediately and turn on the AC while opening all windows for 10 to 20 seconds. Even on the hottest days, the air outside will be cooler than the superheated air trapped inside your car.
This window technique helps the AC system by giving it cooler air to work with from the start, actually speeding up the cooling process.
2. Set the temperature to the lowest setting
(Image: © Shutterstock)
Setting your AC to the lowest temperature and adjusting the fan speed makes the system more efficient and can actually save fuel. In most AC systems, the air is cooled to around 38 degrees regardless of your temperature setting.
When you set the temperature higher, you’re forcing the system to reheat that already-cooled air, which wastes energy and fuel.
Let the system do what it does best, produce maximum cold air, then control your comfort level with the fan speed instead of temperature adjustments.
3. Turn off recirculation mode with passengers
(Image: © Tom’s Guide )
If you have passengers in the back seat, avoid using recirculation mode for extended periods. This setting takes air from the front of the cabin and pulls it back through the system, which keeps the front seats comfortable but can leave rear passengers in stale, warm air.
Use fresh air mode instead to ensure even cooling throughout, especially on longer trips with multiple passengers. Reserve recirculation for when you’re alone or dealing with external odors like traffic fumes.
4. Disable auto start-stop in hot weather
(Image: © Shutterstock)
If your newer car has an auto start-stop feature, consider turning it off during extremely hot weather. While this feature normally saves fuel, it can prevent the AC compressor from running when the engine shuts off at traffic lights or in stop-and-go traffic.
In sweltering conditions, you’ll notice the lack of cool air almost immediately, especially during lengthy stops. The fuel savings from start-stop technology aren’t worth the discomfort when you’re already battling extreme heat.
5. Check and replace your air filter
(Image: © Shutterstock)
A dirty cabin air filter significantly reduces your AC system’s effectiveness by restricting airflow. Check your filter regularly — in most modern cars it’s located behind the glove compartment and relatively easy to access. If you see dirt accumulation on the filter, it’s time for a replacement.
A clean filter not only improves cooling performance but also enhances air quality inside your vehicle. You can save money by replacing the filter yourself rather than paying for dealership service, and it’s typically a simple job that takes just a few minutes.
Now that you’ve learned how you can make your AC stay cooler for longer, why not take a look at our other useful guides?
Check out 7 car cleaning tips to make yours look brand new and how to keep your electric car’s battery healthy.
And don’t miss Google Maps lets you customize your car icon on Android and iOS — here’s how to do it.