Summer usually means two things: hot weather and road trips. It’s a time when you might find yourself stuck in traffic on a highway en route to a weekend getaway. In those moments, you want to get as much cool air into your car as you possibly can. But you might also know that car A/C can use gas more quickly, and gas is not cheap.
Luckily, using the right settings on your car’s climate system — especially one control in particular — can help you out in this situation.
The button or switch you’re looking for is usually next to or underneath the controls for temperature and fan speed. It’s called the air recirculation button, and it shows a picture of a car with an arrow forming a circle.
Turning on the recirculation function keeps the air that’s inside the car moving through the climate system and the cabin air filter over and over. Turning it off, on the other hand, means the car keeps pulling in new air from outside. Using this button helps you in a few ways.
First, you will breathe cleaner air while inside your car. If you’re on the highway and you don’t have the recirculate function on, your car will pull in quite a bit of pollution from the car exhaust around you.
Second, if it’s hot outside, the air conditioning has to work harder to cool down the incoming air, rather than simply keeping steady the air that’s already cooled inside your car. And the extra energy to cool down the incoming air ends up using more fuel. By keeping that recirculate button engaged, you use gas or electricity more slowly, you keep your car cooler, and you stop polluted air from coming in.
To save even more gas, keep the car A/C turned off and crack a window when the temperature outside allows for it. This is especially true if you’re sitting in a parking lot for some reason. Your car can use 8–10% more gas when idling with the A/C on.
While the recirculation button works well in the hotter summer months, you’ll want to make sure you have it switched off in the winter, since this can trap moisture in your car and cause windows to fog. The fresh, dry winter air coming in will be heated by your car and will dry up that condensation to give you a clear view.