When to Use the External Circulation?
2 Answers
Use the external circulation on highways, in suburban areas, or in regions with good air quality. The external circulation refers to the air intake of the air conditioning blower coming from the outside, which supplements fresh air by using a fan to draw external air into the car. This means the external air passage is connected to the car, allowing ventilation, and the air blown by the fan originates from outside the vehicle. The external circulation should be used in conjunction with the car's heating system. When activated, it ensures a continuous supply of fresh air inside the car. During long highway drives with closed windows, the air quality inside the car can deteriorate. In such cases, the external circulation brings in outside air, maintaining a fresh atmosphere inside the vehicle.
After driving for so many years, I've found that the external circulation mode is most suitable for use in good weather, such as clear blue skies with white clouds, as it naturally introduces fresh air, avoiding stuffiness or odor buildup inside the car. Once, during a long highway drive with clean outside air, turning on the external circulation made me feel much more refreshed, breathing smoothly and less prone to fatigue. Additionally, during rain or high humidity, using external circulation helps quickly defog the windshield, preventing blurred vision and potential safety hazards. However, if there are pollution sources outside, like traffic jams with exhaust fumes or strong odors, it's best to switch back to internal circulation to protect yourself. In short, external circulation makes driving more comfortable and healthier, and I often use it to keep the car's interior environment fresh.
