How to Use Car's Internal and External Air Circulation?

[Fred]

Correct usage of car's internal and external air circulation: Use internal circulation in traffic jams and external circulation on highways. The use of internal and external circulation should be combined with air conditioning and heating. Below are detailed explanations of internal and external circulation: 1. The car's fan has two operating modes: external circulation and internal circulation, which can be switched using a toggle switch. 2. External circulation mode uses the fan to draw air from outside the car into the interior, meaning there is airflow between the outside and inside of the car. The air blown by the fan comes from outside, and even if the fan is off, airflow is still drawn into the car while driving, replenishing fresh air inside. When driving in the city and encountering traffic congestion, the car interior can fill with exhaust fumes. 3. Internal circulation mode closes the airflow passage between the inside and outside of the car. Without the fan, there is no airflow circulation, and when the fan is on, the airflow drawn in comes only from inside the car, creating internal airflow circulation. Internal circulation mainly prevents external dust and harmful gases from entering the car, such as when driving through smoke, dust, areas with strong odors, or in heavy traffic, blocking harmful exhaust from vehicles ahead. Another function is to maintain interior temperature.

[SanVera]

As someone who frequently drives long distances, I'm quite familiar with using the air recirculation mode. The operation is actually very simple. Most cars have a button on the climate control panel with an icon resembling a circular arrow or showing separation between inside and outside of the car - pressing it toggles between recirculation and fresh air modes. Personally, I prefer using recirculation mode during traffic jams to prevent external exhaust fumes and dust from entering, such as when driving in the city during rush hour. Switching to recirculation allows the cabin air to circulate internally, improving comfort. When driving on highways or in areas with fresh outdoor air, I press the fresh air button to allow clean air circulation and prevent stuffiness in the cabin. It's important to note that you shouldn't keep recirculation mode on continuously, as CO2 buildup may cause fatigue. Additionally, combining it with temperature adjustment works better: first use recirculation for quick cooling, then switch to fresh air to maintain balance. I've also found that regularly cleaning the cabin air filter improves the efficiency of both modes, especially during allergy seasons. In summary, flexible use of this small feature can significantly enhance driving comfort and health.

[PeterMarie]

I believe paying attention to health aspects is particularly important, as proper use of the air recirculation mode directly impacts daily respiratory safety. Generally, I activate the recirculation mode in areas with severe air pollution, such as industrial zones or construction sites. This ensures air is only filtered within the car, reducing inhalation of harmful particles. For instance, when traveling with family, since children are more sensitive, I prioritize using recirculation to protect their health. When air quality is good, such as near parks or after rain, I switch back to fresh air mode to introduce oxygen and boost alertness. The operation is simple—just locate the recirculation button on the dashboard and try it. I’ve also noticed some new cars come with air purification systems, which work even better with fresh air mode to eliminate bacteria. A crucial reminder is to regularly replace the cabin air filter to prevent bacterial growth, enhancing overall in-car air quality. Choosing the right air circulation mode not only ensures comfort but also prevents health risks.

[StLawson]

I usually focus on energy saving and environmental protection while driving, and using the air recirculation can help save fuel and extend equipment lifespan. The recirculation button is typically located in the air conditioning area, and you can switch modes with just one press. I've found that the recirculation mode allows the air conditioning to adjust the temperature faster, reducing compressor operation time and thus slightly saving fuel. For example, in hot summers, using recirculation first to cool down quickly before switching to fresh air mode maintains stable efficiency. However, be careful not to use recirculation for too long, as it can reduce air circulation and increase health risks. On highways, using fresh air mode allows for natural ventilation, reducing air conditioning load. Regular maintenance of the air conditioning system, such as cleaning the ducts, can also enhance the effect. Properly switching this small feature promotes energy-efficient driving habits.