What is the most fuel-efficient temperature to set your car's AC in summer?

[AugustDella]

Before getting in the car, you should open all windows and doors to let the interior temperature and odors dissipate before starting the engine and turning on the AC. It is recommended to set the AC temperature around 20°C in external circulation mode, not too low as extremely low temperatures will significantly increase fuel consumption. Once the interior temperature cools down, switch the AC to internal circulation mode and you may appropriately adjust the temperature higher based on personal preference. Specific guidelines are as follows: 1. AC vents: Try to direct the AC vents upwards, and avoid placing items like phone holders or car fragrances near the vent openings as they may obstruct airflow and reduce cooling efficiency. 2. AC fuel consumption: The slower the interior temperature drops, the higher the fuel consumption will be. Always remember to turn off the AC before parking and shutting off the engine at your destination to prevent the AC from starting automatically when the car is restarted, which can also lead to increased fuel consumption.

[IrisLee]

When it comes to saving fuel while driving in summer, as an experienced driver with years of practice, I've found that setting the air conditioning between 23 to 25 degrees is most ideal. Setting the temperature too high makes the cabin uncomfortably hot, but setting it too low, like 18 degrees, forces the AC compressor to work excessively, putting heavy load on the engine and consuming more fuel. I remember during a recent heatwave, I set it at 24 degrees with auto mode, and my fuel consumption was nearly 10% lower than usual—cool and cost-effective. It's best to open the windows for a few minutes to ventilate and cool down the car before closing them and turning on the AC, avoiding high-load operation of the compressor right after startup. Also, check if the cabin air filter is clean; a dirty one reduces efficiency and increases fuel consumption. During traffic jams, avoid running the AC at full capacity—slightly raising the temperature can save a lot on fuel. These small habits, accumulated over time, benefit both your wallet and your car.

[VanEmersyn]

As an environmentally-conscious young person, I believe that using the air conditioning in summer should balance comfort with fuel efficiency. Setting it around 24°C is generally ideal. For every degree lower, fuel consumption may increase by over 5%. The more frequently the compressor operates, the more fuel it consumes, and it also emits more exhaust gases that pollute the environment. I prefer using the external circulation mode instead of maintaining a consistently low temperature, as it provides ventilation while reducing the load. Planning routes to avoid traffic congestion before heading out helps minimize AC usage time. Turning off the AC while briefly waiting in the car and using window films to reflect some heat can also contribute to fuel savings. These small adjustments add up, protecting the planet while saving money—why not do it?

[AnthonyLynn]

When driving my kids to and from school regularly, I've found that the car's air conditioning shouldn't be set too low or too high in summer. Setting it at 23°C strikes the perfect balance: too cold and the kids might catch a chill or fever, too hot and it's stuffy, uncomfortable, and consumes more fuel. My routine is to roll down the windows for a few minutes after starting the car to let the heat out before closing them and turning on the AC at 23°C in auto mode, which adjusts the fan speed automatically, saving a good amount of fuel. Keeping the AC filter clean prevents blockages that can force the compressor to work harder and use more fuel. Also, avoiding heavy loads and accelerating gently by easing onto the throttle helps reduce fuel consumption. Simple and practical, keeping the whole family comfortable.

[SanCali]

Having played with cars for so many years, I've researched how to save fuel with air conditioning. The key is not to set the temperature too low; 25 degrees is recommended as optimal: the AC compressor works less, reducing engine load and naturally lowering fuel consumption. The principle is simple—each degree lower makes the compressor run more, consuming extra fuel. I tested driving at 25 degrees on a 35-degree day and saved nearly 15% fuel compared to 20 degrees. Other techniques should also be applied, such as regular AC system maintenance, ensuring sufficient refrigerant, and using auto mode to avoid manually lowering fan speed. Parking in the shade prevents direct sunlight, keeping cabin temperatures from rising too much, so the AC doesn’t have to work as hard. These small tips make a big difference in daily driving.

[OGenevieve]

When I was younger and driving, setting the AC to 24°C was enough—saving money and fuel. Lower temperatures increase compressor load and engine fuel consumption, especially noticeable during summer traffic jams. Around 25°C offers just the right comfort with efficient AC operation and lower fuel usage. I make it a habit to open the windows first to cool down the car before closing them and turning on the AC, reducing the initial load. Using a sunshade inside the car prevents excessive heat, so the AC doesn’t need to be set too low. Regular oil changes and maintaining proper tire pressure also contribute to overall fuel savings. Sticking to these simple methods can save dozens of dollars on fuel each month—proven old tricks that really work.