Your car’s air-conditioning system has one job—to keep you cool. But during a summer scorcher, it may seem like it’s barely up to the task. And even at those times, it’s eating up gas: The EPA estimates that using A/C in very hot conditions can reduce fuel economy by as much as 25 percent for a conventional vehicle. (It also zaps battery life in electrics and hybrids.)
Here’s why: Whenever you flip the switch, the system pulls in air from either the cabin or outdoors, extracts the heat and moisture from it, and pushes it out through vents. And the heart of this system is a compressor, which draws energy from the engine. So whenever you’re using the A/C, the engine has to work harder—and you burn more fuel.
But a few easy tips can help you save gas—and money—while making you feel cooler faster. Here’s what the pros recommend.
Park Smart
A car’s A/C system can only reduce the cabin temperature by approximately 40 degrees on average, says Jill Trotta, head of industry advocacy and sales for RepairPal. (Though of course, the longer you drive, the cooler the air will become.) If you park in a shady spot, the interior will start out cooler and the A/C will have less work to do. If the cabin is warm, roll down the windows and let the hot air escape before you rev up the A/C.
Set It To Recirculate
“Recirculation is probably the best way to maximize the A/C,” says Trotta. The benefit of recirculation is that the A/C system is pulling air only from within the cabin. So if it’s roasting outside but you already have the cabin down to a pleasant 72 degrees, the A/C will have to chill only that cooler air within the car. You’ll save on gas, too: Once the interior reaches the set temperature, the A/C compressor will turn off, reducing the load on the engine.
Skip Pre-Cooling
It may be more comfortable to cool your car before you’re underway, but running the A/C when the car’s not moving is highly inefficient. “Air conditioning will perform optimally when there’s airflow, like when you’re driving down the road,” says Timothy Hatcher, director of technical operations for the Automotive Maintenance & Repair Association. So wait until you’re already cruising before you turn it on. In an electric or hybrid, pre-cooling reduces the battery life, so either avoid the practice or stay plugged into the charger when you do it.
Change Your Cabin Air Filters On Schedule
The cabin air filters remove dirt and dust from the air that comes out of the vents. When a filter gets dirty, it restricts the air trying to pass through, says Hatcher. So replace the cabin air filters according to the schedule in your owner’s manual, which is probably every year or two, or every 15,000–20,000 miles.
Don’t Ignore Leaks
The biggest misconception about A/C systems, says Hatcher, is that if they’re low on refrigerant, you just need to add more (a process called recharging). But the system is sealed; nothing should be going in or out. “Adding refrigerant isn’t normal, and it isn’t maintenance,” says Hatcher. “It’s an indication of some other issue.” If yours is low, visit a professional certified in air-conditioning maintenance and repair to check it out.
Another way to keep your cool (and peace of mind)? Download the GEICO Mobile app for help at your fingertips—from roadside assistance to help finding your car and more!
Read more: Check out these other smart ways to get better gas mileage.
By Julie Anne Russell
Mark says,
The air conditioning tips would be helpful if I knew what you meant.. What is recirculation? here is that control.. I don’t see one. I have a recent Nissan Altima. It air unit is fantastic. Cools very quickly. I don’t know that you mean by recirculating the air first. Yes I agree letting the car engine warm up first & rolling before starting the air is a good idea.. Tell me how I recirculate the air first…
Carlos Pacheco says,
Very interesting ideed. I try to drive with the windows open for short time before turning the A/C to cool the car. Also try to park under trees or shades when posible., that really cools the car.
Rosa A. Veras says,
Thanks for you information.
Appreciate
JUDY clutter says,
Your articles are so informative. Thanks
Robrt Beggs3@gmail.com says,
Super fine AC recommendations — right on target!!
Thank you!
Thornton says,
Very informative article.
Brian W says,
Myth busters proved that you don’t use any more fuel if your AC is off or on. The best way to quickly cool your car is not to rum your fan on max but one down from it. The faster the fan blows the air out makes the cooling prosses take much longer. By running the fan at half it’s full power the air moves slower from the compression system giving more time to cool the air coming in. One more note. Pre cooling your car for up to 30 mins will cost you less then $2.00 for 4 and 6 cyl gas engines and not more then $5.00 for a Cummings for 30 mins. I’d say it’s absolutely worth the comfort. We spend more on coffee during our comute. I’d say it’s worth the few bucks for a few months out of the year. Same In winter. I will pre warm the car for up to 30 mins twice or more a day and there is realy no difference in my monthly fuel cost year round. I’ve been watching my fuel consumption very closely and for me this is what worse best.
Glenn Heilweil says,
I spent 20 years designing and engineering refrigerators.A first cousin to air conditioners. YOU HAVE MISSED THE MOST IMPORTANT TIP. Many peopled not like air blowing in their face. They point the vents away from them, maximize the fan blower and cool the rest of the car in order to cool themselves. With the air blowing full force, the cooling coil takes much longer to cool down and you triple thecooling effort in cooling the whole car instead of cooling the driver and any passenger. Triple the running time, triple the stress on the system and triple the loss of fuel efficiency and burden on the car. INSTEAD point the vent directly on you, lower the fan speed to almost minimum. You will cool yourself much, much faster, with much better fuel efficiency and far less stress on the car.
Timothy Brooks says,
Helpful thank you
Adrienne Riviere says,
Thank you for these AC-operating tips. As per suggestion #2, what is the setting for “recirculating” air for AC system?
Brigitte Strong says,
Thank you for this great information. Glad to be with Geico
Hope Thorne says,
Thank you appreciated the tips.
Waseem says,
Another way to cool down immediatly is open all doors before you sit in and it take only ew second to escape the eat faster.
Soula K Dortch says,
Thanks for sharing this info.
Kabir Hussain says,
Thanks for tips you are the best