What are the functions of the internal and external circulation?

[DeKatherine]

Internal circulation prevents external dust and harmful gases from entering the vehicle; external circulation provides fresh air to the vehicle. The differences between internal and external circulation are as follows: 1. Different icons: Internal circulation allows the air inside the vehicle to circulate when the vehicle is closed, and the icon is a closed car interior with a circulating arrow; while external circulation allows the air outside the vehicle to flow into the vehicle, and the icon is an unclosed car with an external air arrow pointing into the vehicle. 2. Different definitions: Internal circulation refers to the air inside the vehicle being heated or cooled and then sent back into the vehicle; external circulation refers to the air outside the vehicle being heated or cooled and then sent into the vehicle, which means gas exchange between the inside and outside of the vehicle.

[DelTanner]

I remember that after driving for so many years, switching between the internal and external air circulation is super important. Internal circulation recirculates the air inside the car, making the air conditioning work faster. For example, after getting into a car that's been baking in the summer sun, turning on the internal circulation can cool it down in just a few minutes. External circulation draws in fresh air from outside, preventing the oxygen inside the car from running out and making people feel drowsy. I often use external circulation on highways to keep the air fresh, especially during long drives, switching to internal circulation at rest stops to maintain the temperature. It's also important to pay attention to areas with poor air quality, like tunnels or traffic jams—using internal circulation blocks outside exhaust fumes and dust, keeping pollutants out. I've seen some beginners keep the internal circulation on all the time, leading to foggy windshields due to the temperature difference inside and outside. Regularly switching between the two modes helps the car last longer and saves a bit on fuel. These little tips really make driving much more comfortable—just develop good habits.

[SanVictoria]

I always care about environmental protection and energy efficiency while driving, so understanding the use of recirculation mode is essential. Recirculation mode reuses the air inside the car, reducing the workload of the air conditioning compressor, which saves electricity and fuel. Fresh air mode draws in outside air, suitable for when the air quality is good or ventilation is needed. Living in the suburbs, I switch to fresh air mode in the morning to enjoy the fresh breeze; in city traffic, I switch to recirculation mode to block exhaust pollution. This not only saves fuel but also reduces my carbon footprint, making my car greener overall. Additionally, these modes affect air quality inside the car—recirculation prevents dust and odors, while fresh air mode prevents CO₂ buildup that can cause driver fatigue. I recommend adjusting based on weather: use fresh air mode on rainy or foggy days to defog faster. In short, smart switching reduces energy consumption, protects the environment, and enhances safety and comfort. These small details add up to significant environmental benefits.

[VanAlaina]

As a homemaker, I pay special attention to the air recirculation mode when traveling with my kids. The recirculation mode helps the air conditioning heat up or cool down quickly, reduces dust and allergens entering the car, which is better for my baby's health. The fresh air mode introduces outside air, preventing fatigue or headaches from being cooped up for too long. Simply put, recirculation maintains a clean environment while fresh air mode provides ventilation. In summer, I use recirculation on the way to the mall to keep the heat out; in winter, I switch to fresh air mode to defog. Once on a long drive using only recirculation, the air became stale and made us drowsy—switching to fresh air mode immediately helped. I recommend regularly checking the system to ensure it's not blocked, maintaining proper airflow. This makes a big difference in family comfort.