Should You Use Internal or External Air Circulation When There's an Odor in the Car?

[MacStella]

Use external air circulation. The differences between internal and external air circulation are as follows: 1. Different working principles: Internal circulation means the air inside the car is heated or cooled and then recirculated within the vehicle; external circulation involves drawing in outside air, heating or cooling it, and then sending it into the car, effectively exchanging air between the inside and outside of the vehicle. 2. Different usage methods: When turning on the air conditioning for cooling or heating, you can first activate internal circulation to quickly lower or raise the temperature inside the car. Once the temperature stabilizes, appropriately switch to external circulation to exchange air with the outside. If the outside air quality is poor, such as in heavy traffic with lots of exhaust fumes or in underground parking lots, avoid using external circulation. When driving on the highway, never open the windows; instead, use external circulation. If you feel stuffy inside the car when the outside air is good, switch to external circulation for ventilation.