Open Today! Sales: 9am-8pmService: 7am-6pm

Does Car AC Use Gas?

Car AC Vents

Does car AC use gas? It may not be obvious to some St Louis drivers, but your car’s air conditioning system does, in fact, use gas just like many of the other features. Your AC draws power from the alternator, which in turn is powered by the engine. Fuel will be used to power this process. However, in some situations using your AC can actually be the most efficient. Learn more about your car’s air conditioning system below and contact our service department to maintain your smooth Jefferson County commute.


How Car AC Works

So, how does car AC use gas? All car air conditioning systems run on a high-pressure gas called refrigerant. Regardless of your car’s make, you will find these components in your AC system:

  • Compressor — compresses the refrigerant into a fluid, allowing the refrigerant to flow through the line to the condenser.
  • Condenser — removes the heat from the refrigerant and pushes it along to the expansion valve or orifice tube.
  • Expansion valve or orifice tube — returns the refrigerant to its original gaseous state and moves it to the receiver/drier or accumulator.
  • Receiver/drier or accumulator — removes moisture from the refrigerant and transfers it to the evaporator.
  • Evaporator — pulls heat from the air passing through its core and transfers it into the refrigerant, resulting in cold air flowing beyond the evaporator.

Can Using Car AC Be Fuel-Efficient?

Based on recommendations from the EPA, using your AC while driving at highway speeds is more fuel-efficient than leaving the windows down. While it can be refreshing to roll down the windows while cruising through St Charles, it also creates more drag. When this happens, your engine has to work harder and burns more fuel to maintain higher speeds. So if you are looking to maximize your fuel economy, using your AC while on the highway will not be wasteful.

Other Ways to Improve Fuel Economy

Along with keeping the windows up on the highway, there are a ton of ways to improve your fuel economy. Check out our service tips to keep your vehicle running smoothly and these suggestions for efficiency:

  • Brake gradually
  • Make sure your car’s tires are properly inflated and aligned
  • Don’t idle for more than 30 seconds
  • Pack light
  • Use sun reflectors if you’re parking in a sunny spot
  • Don’t use cheap engine oil
  • Reduce your speed and drive in a higher gear
Silver 2020 Kia Sorento Driving Through Field

Get AC Service Suntrup Kia South!

Still have lingering questions about your car’s AC system? Think your air conditioning may need service? Contact us today! Our expert technicians can handle any AC issues to keep you comfortable on every drive. We offer service specials year-round to help you stick to your budget. Visit us in St. Louis for all of your car care needs today!


Kia Service Coupons

Free 1-Day Rental Vehicle

FREE

Valid with any repair or service of $300 or more. One day only. Applies to same day service. Subject to availability.

Restrictions may apply. Must present coupon at time of service write-up. May not be combined with other coupons or discounts. May not be used on previous purchases. See dealer for details.

Tire Special

ALL TIRES ON SALE!

We won’t be beat on prices.

Shop now: Kia Tire Source


Explore Our Models

  • Your 2026 Kia Sorento Price Guide: What Every Trim Costs in St. Louis

      The 2026 Kia Sorento is one of the most flexible three-row SUVs in its class, and Suntrup Kia South carries the full lineup with competitive pricing for St. Louis families. Across eight gas configurations, the 2026 Kia Sorento price starts at $33,635 for the LX and climbs to $49,035 for the top-tier X-Pro SX…

  • Your 2026 Kia Sportage Price Guide: What Every Trim Costs in St. Louis

      Shopping for a compact SUV in St. Louis? The 2026 Kia Sportage arrives at Suntrup Kia South with a sharper look, upgraded standard technology across every trim, and some of the most competitive pricing in its class. The 2026 Kia Sportage price starts at $30,135 for the gas LX including destination, with six gas…

  • 2026 Kia Sorento Hybrid vs. Honda CR-V Hybrid: Do You Need a Third Row?

    The 2026 Kia Sorento Hybrid and the 2026 Honda CR-V Hybrid both show up on St. Louis shoppers’ short lists for the same reason: strong fuel economy in a hybrid SUV without an EV’s charging hassle. But they’re built for different jobs. The CR-V Hybrid is a five-seat compact SUV with a lower starting price…

Trade-In

Suntrup Kia South 38.5159372, -90.3443184.