Is the 'a' button for internal or external air circulation?
2 Answers
The 'a' button is neither for internal nor external air circulation. This 'a' button activates the automatic mode, where sensors will automatically determine whether to use external or internal air circulation based on air quality. The car air conditioning system is a crucial component in vehicles, differing from home air conditioners in that it features both internal and external circulation modes. During high-speed driving when opening windows is inconvenient, you can activate the external circulation mode. When passing through areas with heavy dust or during traffic jams, the internal circulation mode can be used. If external circulation is enabled during traffic congestion, exhaust fumes may enter the cabin. It's essential to regularly replace the cabin air filter during routine vehicle use, as failure to do so may affect passenger health and reduce air conditioning efficiency.
I've been driving a taxi for over a decade and know this issue well. The button with an 'A' is the auto-recirculation mode, which isn't purely internal or external circulation. The vehicle automatically switches based on air quality sensors – like cutting to internal circulation to block pollution when stuck in heavy traffic with exhaust fumes, or switching to external circulation for fresh air during highway driving. In summer with AC on, it prioritizes internal circulation for quick cooling before switching to external circulation to balance humidity. For manual control, look for the car symbol: an arrow pointing into the car means internal circulation, while an arrow coming from outside indicates external circulation. Auto mode is quite hassle-free, but I'd recommend manually switching to internal circulation in areas with poor air quality for safety.
