Should the Air Conditioner Use Internal or External Circulation When Driving in the Rain?

[OPenelope]

It is better to use external circulation when driving in the rain. Here are the specific details about using the air conditioner on rainy days: External Circulation: On rainy days when the weather is cold, fog tends to form on both side windows, obstructing the driver's view. Using external circulation helps expel the moisture exhaled by passengers out of the car, making it less likely for the cold outside air to condense. Internal Circulation Can Feel Stuffy: With the windows closed, internal circulation recirculates the air inside the car through the fan. Since the passage for outside air is closed, no fresh air enters, making the air feel stuffy. External circulation, on the other hand, opens the passage for outside air to enter while circulating the air inside the car, keeping the air fresher.