Which One is the External Circulation?

[LucasLynn]

The external circulation symbol is an arrow pointing from outside the car to the inside; the internal circulation symbol is a circular arrow inside a car graphic. Internal Circulation: The function of internal circulation is to prevent dust and odors from being drawn into the car through external circulation. Therefore, a control system is set up to close the external circulation air duct, blocking polluted air from outside the car. External Circulation: Since the interior of the car forms a relatively sealed environment, prolonged exposure to this environment can lead to oxygen deprivation. To address this, the air conditioning system includes an additional air duct that draws in fresh air from outside the car. This air then passes through the air conditioning evaporator or heater core, delivering either cool or warm air.

[DelKeegan]

The external circulation is a mode in the car's air conditioning settings that allows air from outside the vehicle to enter the cabin. I find this feature particularly useful in my daily driving, especially when the air quality is good, such as in suburban or rural areas. It directly draws fresh air into the car, making the interior feel fresher and more natural. Compared to the internal circulation, which only recirculates air within the car, the external circulation prevents the cabin air from becoming stale or stuffy. This is especially important during long summer drives—without it, carbon dioxide can accumulate, leading to passenger fatigue. I often use it to deal with fogged-up windows: on rainy or cold days, turning on the external circulation quickly blows in dry outside air, effectively clearing the fog. I recommend drivers switch between modes wisely: use internal circulation in heavy traffic or polluted urban areas to avoid inhaling dirty air, but opt for external circulation when the air is clean. This small habit can make driving more comfortable and healthier, while also helping maintain alertness.

[LaRylee]

The external circulation refers to the ventilation mode where the car's air conditioning system draws in air from the external environment. As a driver who frequently takes long-distance trips, I highly value this feature. Simply put, when the external circulation is turned on, the car draws air from outside into the cabin, which effectively helps with dehumidification and odor removal. I understand that technically, it involves an air intake and a valve setup: external air enters through the grille, is filtered by the air conditioning system, and then delivered to the cabin. In practical driving, I particularly recommend using it on highways or in dry weather because it utilizes natural wind pressure to reduce the load on the air conditioning compressor, thereby improving fuel efficiency. Compared to pure internal circulation, it ensures a fresh oxygen supply, preventing passengers from feeling dizzy in a confined space. However, be cautious not to use it in areas with smoke or dust. The air conditioning button in my car is easy to operate, usually located near the steering wheel or on the center console, with an icon showing an arrow pointing into the car from outside. Properly combining it with internal circulation can optimize the cabin environment.

[LaDamian]

The external circulation mode allows the car's air conditioning system to draw in fresh air from outside the vehicle. I consider this crucial for driving safety as it maintains air circulation inside the cabin. When driving my car, if I need ventilation without opening windows, external circulation is the ideal choice: it supplies oxygen and prevents stuffiness or drowsiness. It's particularly effective for quickly resolving window fogging or unpleasant odors. From a health perspective, prolonged use of internal circulation can increase CO2 levels, leading to dizziness; external circulation prevents this. When using this function, activate it in areas with clean air and deactivate in polluted zones. Mastering this simple feature significantly enhances driving comfort.