Choosing Between Internal and External Air Circulation for Car Air Conditioning in Winter

[StJaxon]

In winter, use internal circulation when turning on the heater. After starting the car, wait approximately 8-15 minutes for the water temperature to reach normal levels, then you can turn on the heater and switch the air conditioning to internal circulation mode. Difference between internal and external circulation: Internal circulation works by closing the airflow channels between the inside and outside of the vehicle. When the air conditioning is on, only the air inside the car circulates. Without the fan running, there is no air movement inside the cabin. External circulation operates by using the fan to exchange air between the inside and outside of the vehicle, bringing fresh air in from outside and expelling stale air from inside. Even without the fan running, the vehicle can still allow airflow to refresh the cabin air. Application scenarios for internal and external circulation: When driving on highways for extended periods, the air inside the vehicle can become stale, and opening windows may create excessive wind noise. In such cases, switching to external circulation can refresh the cabin air while filtering out poor-quality outside air. When driving in urban areas during rain, snow, or when outside air quality is poor, closing the windows and using the internal circulation mode of the car's air conditioning is a good choice. This blocks out poor-quality outside air, prevents breathing discomfort, helps maintain cool temperatures in summer, and keeps the cabin warm in winter.