Should You Use Internal or External Air Circulation for Car AC in Winter?
2 Answers
Whether to use internal or external air circulation for the car AC in winter depends on the situation. The use of internal and external circulation is not fixed, and maintaining one mode all the time can affect your health. It's important to determine when to use internal circulation and when to switch to external circulation based on actual conditions. Use internal circulation in traffic jams and external circulation on highways. The use of internal and external circulation should be combined with the AC and heater. External circulation allows you to breathe fresh air from outside. If the warm air feels too hot in winter, you can turn off the fan and open the external circulation to maintain the interior temperature while getting fresh air, which feels more comfortable. However, if the AC is used to lower the interior temperature, avoid using external circulation at this time. You can occasionally switch to external circulation to bring in fresh air.
As a seasoned commuter driver, I know all too well about using the car heater in winter. Turning on recirculation mode does warm up the cabin faster, especially when you first get in the freezing car - hot air blows out and you feel warm within seconds as the temperature rises rapidly. But this method has major drawbacks - the windows keep fogging up, creating dangerous visibility issues. So my advice is: use a mixed approach. Start with recirculation for a few minutes to warm up, then immediately switch to fresh air mode to let dry outside air in; this improves air circulation, reduces humidity, prevents window fogging, and makes driving much safer. Using recirculation alone for extended periods makes the air stuffy and stale, causing drowsiness and dizziness, and worsens breathing during winter smog. If your car has automatic defogging, remember to activate it as it intelligently adjusts air circulation. Never take shortcuts by using recirculation alone - impaired visibility on highways can have serious consequences. Maintaining clear visibility is absolutely crucial.
