Use Internal or External Air Circulation When Turning on the AC?

[LaJames]

When turning on the AC, alternate between internal and external air circulation. The correct approach for using AC in summer: After getting in the car, first open the windows to ventilate and allow the interior to cool down. Open the doors and windows to lower the interior temperature before turning on the AC. Start with internal circulation to achieve the fastest cooling. Once the interior temperature drops to a comfortable level, switch to external circulation to maintain fresh air inside the car. Internal circulation means the air blown by the fan only circulates within the car, with no outside air involved. This method saves fuel and cools quickly but has the disadvantage of reducing air quality inside the car. External circulation means the fan draws air from outside the car and blows it inside, which helps maintain fresh air but consumes more fuel and cools more slowly.

[LaEmery]

When driving in the scorching summer heat, I prefer using the recirculation mode for the air conditioning first, as it quickly cools the air inside the car and blocks the hot air outside. Especially in high-temperature environments, it can rapidly enhance the cooling effect and save on cooling time. The initial cooling stage is incredibly effective, as the residual cold air inside the car circulates directly, reducing the load on the AC and saving fuel. However, remember to switch to the fresh air mode after prolonged use—about every 15 minutes—to avoid the buildup of carbon dioxide inside the car, which can cause stuffiness and fatigue. Safety is also important; if the outside air is clean and fresh, using the fresh air mode maintains airflow and prevents drowsiness. Overall, starting with recirculation to cool the car down and then switching to fresh air for better ventilation is a smart choice for summer driving.

[DelAlexandra]

As a health-conscious driver, the choice between using the air conditioning's internal or external circulation is crucial. In areas with poor air quality, such as during haze or urban traffic peaks, I prefer using the internal circulation to avoid inhaling pollutants and exhaust fumes, protecting respiratory health. Indeed, the internal circulation cools down faster when the AC is turned on, but keeping the air exchange closed for too long can increase carbon dioxide levels, leading to dizziness or drowsiness, which affects driving safety. It's advisable to switch to external circulation for a few minutes periodically to ventilate and ensure sufficient oxygen inside the car. When the external environment is fresh, prioritize external circulation to maintain natural airflow, making breathing more comfortable. Balancing the use of internal and external circulation can keep both body and mind in optimal condition.

[EmersonLynn]

In congested urban traffic conditions, I highly recommend using the recirculation mode when turning on the air conditioning. During traffic jams, exhaust fumes are pervasive, and using the fresh air mode will introduce external pollutants, worsening the air quality inside the car. The recirculation mode blocks these pollutants while improving cooling efficiency, allowing the cabin to reach a comfortable temperature within minutes. This is especially beneficial in high-density traffic areas, as it reduces inhalation of harmful particles, protects lung health, and enhances driver concentration. However, avoid continuous recirculation for over 20 minutes to prevent stale air and driver fatigue. Switch to fresh air mode when traffic flows smoothly. Mastering this switching strategy is crucial for urban driving.