What circulation mode should be used when turning on the car's air conditioning?
3 Answers
When using the car's air conditioning for cooling, the internal circulation mode should be activated. 1. Internal circulation: This mode means the air conditioning system draws air from inside the vehicle, cools it through the compressor, and then recirculates it. The advantage of this circulation type is that it allows for rapid cooling or heating of the car interior. However, the drawback is that prolonged use of internal circulation may lead to decreased oxygen levels and increased carbon dioxide concentration inside the vehicle. 2. External circulation: This mode introduces fresh air from outside to improve air quality inside the car. It's typically used during winter defrosting or summer defogging operations, as outside air contains higher oxygen levels and is drier, making it more effective for these purposes.
As a driver who frequently takes long-distance trips, I believe that when using the air conditioning in summer, the recirculation mode should be prioritized. This is because recirculation repeatedly cools the air inside the car, which cools down the interior very quickly, especially when it's scorching hot outside. However, prolonged use can make the air inside stuffy and lead to a buildup of carbon dioxide, making people drowsy. So, once the temperature drops, I usually switch to the fresh air mode to let in fresh air for ventilation. Additionally, if there are unpleasant odors or pollution outside, such as when stuck in a tunnel, I maintain recirculation to avoid inhaling exhaust fumes. On the highway, where opening windows is uncomfortable, I use fresh air mode to keep the air fresh. Remember, switching modes every 20 minutes is ideal—it saves fuel and keeps you healthy, preventing fatigue during long drives.
I'm most concerned about high fuel consumption when driving, so I always use the recirculation mode when the air conditioning is on. This mode only cools the air inside the car without needing to process external hot air, which reduces the compressor's workload and significantly saves fuel. Based on my own tests, using recirculation mode saves about 10% in fuel costs compared to fresh air mode, which adds up to noticeable monthly savings. Of course, prolonged use of recirculation can lead to stale air and health risks, so I typically switch to fresh air mode for a few minutes after 5 minutes of cooling. During times of poor external air quality, like urban rush hour traffic, I prioritize recirculation mode; in fresh weather, I use fresh air mode for ventilation. This approach is both energy-efficient and eco-friendly, and it also helps extend the air conditioning system's lifespan.
