What are the differences between vehicle air recirculation and fresh air mode?
2 Answers
The differences between vehicle air recirculation and fresh air mode are as follows: 1. Different working principles: Recirculation means the air inside the vehicle is heated or cooled and then recirculated back into the cabin; Fresh air mode draws outside air into the vehicle after heating or cooling it, achieving air exchange between the interior and exterior. 2. Different usage methods: When initially turning on AC cooling or heating, you can first activate recirculation to quickly lower or raise the cabin temperature; After temperature stabilizes, appropriately switch to fresh air mode for ventilation; Avoid using fresh air mode when outside air quality is poor, such as in heavy traffic with exhaust fumes or poorly ventilated underground parking. When driving on highways, never open windows - simply use fresh air mode instead. When outside air is clean but the cabin feels stuffy, promptly switch to fresh air mode for ventilation.
The difference between the car's internal and external air circulation is simply the source of air. Having driven for years, I know that internal circulation recirculates the air inside the car. It's usually activated by pressing a button and is ideal for quick cooling or heating, like turning on the AC in summer and switching to internal circulation to prevent hot air from entering. External circulation draws in outside air, which is great for fresh air or defogging, such as using it on highways to avoid wind noise from open windows. I usually switch based on the situation: in city traffic jams, I use internal circulation to reduce exhaust fumes and prevent dizziness; in open outdoor areas, I switch to external circulation for fresh air. However, prolonged use of internal circulation can make the air stuffy and increase CO2 levels in the car, affecting concentration. That's why the car's AC system is well-designed and practical.
