Should the Internal Circulation be Turned On When Using the Car Air Conditioner?

[ValerieRose]

When using the car air conditioner, it is advisable to turn on the internal circulation. This helps reduce the entry of particulate matter. Overview: The car air-conditioning device (air-conditioning-device), commonly referred to as car air conditioning, is used to adjust and control the temperature, humidity, air cleanliness, and air flow inside the car cabin to the optimal state. Functions: The car air conditioner provides a comfortable riding environment for the driver, reducing travel fatigue; it also creates favorable working conditions for the driver, ensuring driving safety. The car air conditioning system typically includes a cooling device, heating device, and ventilation device.

[LorenzoFitz]

When driving with the AC on, I prefer to turn on the recirculation button first. This allows the cool air to circulate quickly inside the car, making it much more efficient than using the fresh air mode. Especially during summer when temperatures hit 40°C, just a few minutes of recirculation can cool down the interior. But remember not to keep it on continuously—switch to fresh air mode for a few minutes after about 20 minutes to prevent window fogging. During traffic jams, always use recirculation to avoid exhaust fumes from the car ahead. Last time I forgot to turn it on, the AC felt like a heater even after 30 minutes, and the fuel consumption skyrocketed—it was heartbreaking!

[LondynMarie]

As a driver who frequently takes long-distance trips, the recirculation mode is my go-to tool for temperature control. Turning on recirculation when using air conditioning doubles the cooling speed, which is especially useful on highways. However, I always check if recirculation is activated when driving through tunnels or stuck in traffic queues. Last year, I was stuck on the highway for three hours—without recirculation, the exhaust fumes would have been suffocating. But don’t keep it on all the time; it’s best to switch to fresh air mode for about 10 minutes every hour to prevent windshield fogging and maintain visibility. Nowadays, newer cars with automatic climate control just require pressing the AUTO button—it intelligently switches between circulation modes, making things much easier.

[LaneFitz]

I noticed many people overlook the recirculation function when using air conditioning. Actually, pressing the recirculation button is particularly important when turning on the AC. Especially right after starting the vehicle, using recirculation allows the cool air to directly lower the temperature of the air inside the car, without the need to work hard cooling down the hot air coming from outside. However, avoid using it for extended periods, as high carbon dioxide levels inside the cabin can make people drowsy. My habit is to use recirculation for 20 minutes and then turn it off for a few minutes to let fresh air in. Remember to turn off recirculation when defogging on rainy days for quicker results. Keep this tip in mind, and you can save a lot of fuel when using the AC.

[SanZachary]

Whether to use the internal air circulation when turning on the AC depends on the situation. When you first get in the car and it's extremely hot inside, turning on the internal circulation can cool down the car much faster than just using the AC. However, keeping it on for too long can make the air stuffy. Once, I drove a long distance with the internal circulation on and later felt dizzy and headache, only to realize it was due to poor air circulation. Now, I turn off the internal circulation every half hour to let in fresh air for a few minutes. On rainy days when the windshield fogs up, you must use the external circulation to quickly remove the moisture. If it's a new car with an automatic AC system, simply pressing the AUTO button is the easiest—the system will automatically switch between internal and external circulation based on temperature and humidity.

[DelRhett]

Using the air conditioning with recirculation mode does save more fuel. I personally tested it and found that on the same route, using recirculation mode saves about 15% more fuel compared to just using the air conditioning, because the compressor doesn't have to deal with the hot outside air. However, this method isn't suitable for all situations: when traveling with elderly or children, you need to switch off recirculation more frequently for ventilation; people with allergic rhinitis should use recirculation to filter the air when there's a lot of dust outside; remember to switch to outside air circulation when refueling at a gas station to prevent fuel vapors from entering. Also, before using recirculation mode, make sure to check if the air filter is clean, as a clogged filter can actually worsen air circulation.