Is it better to use internal or external air circulation when driving in winter?

[Judy]

Whether to use internal or external air circulation when driving with the heater on in winter depends on the specific situation. Here are detailed methods for choosing between internal and external circulation: 1. Turn on internal circulation when the outside air quality is poor, when quickly heating the car interior, or when needing to maintain warmth inside the car. Internal circulation uses the existing air inside the car for circulation. Its purpose is to prevent harmful outside elements from entering while also helping to retain warmth. 2. Use external circulation when the outside air is fresh, or when the car has been using internal circulation for an extended period and requires fresh air. External circulation uses a fan to draw outside air into the car, creating airflow between the outside and inside. Even without the fan running, the movement of the car will naturally draw in outside air, replenishing the fresh air inside. 3. When driving on highways for long periods, prolonged lack of air exchange can lead to stale air inside the car. In such cases, it's necessary to turn on external circulation to ensure timely air renewal.

[DiValeria]

When driving in winter, I often struggle with the choice between recirculation and fresh air mode. Fresh air mode is my preferred option because the outside air is dry, effectively preventing window fogging and providing much clearer visibility. Fogging is a common issue in winter, especially on rainy or snowy days. Using recirculation can cause moisture to accumulate inside the car, blurring vision and increasing risks. Safety comes first—ensuring clear visibility of road conditions helps avoid accidents. Of course, when the car is too cold, you can start with a few minutes of recirculation to quickly warm up, then switch to fresh air mode to maintain air freshness. Don’t forget to regularly check the air conditioning system to ensure it works properly for better defogging, making driving safer and more reassuring.