Should the Car Air Conditioner Use Internal or External Circulation in Winter?

[JuniperLynn]

In winter, the car air conditioner should use internal circulation. The function of internal circulation is to effectively and promptly prevent external dust and harmful gases from entering the vehicle, providing faster cooling and heating effects. External circulation serves to replenish fresh air, maintaining air flow between the inside and outside of the vehicle, which helps keep the cabin air clean. The car air conditioner's internal circulation is located below the front dashboard in the driver's compartment, while the external circulation is situated below the windshield on the passenger side in the engine compartment. The car air conditioner is used to regulate and control the temperature, humidity, air cleanliness, and air flow inside the vehicle cabin to an optimal state, providing a comfortable environment for passengers and reducing travel fatigue.

[DeJoy]

In winter driving, I always recommend prioritizing the use of the recirculation mode, as it quickly warms up the car interior and reduces heat loss. Especially in cold winds, getting into a warm car faster helps avoid shivering. However, don’t keep the recirculation mode on for too long, as the air inside the car can become stale, making it hard to breathe, and may also cause the windshield to fog up, blurring your vision—that’s dangerous while driving! On highways or in areas with good air quality, I often switch to the fresh air mode to let in outside air, which helps defog the windows. With less air pollution in winter, you can also breathe in fresh outdoor air, reducing the risk of carbon monoxide buildup. Remember, it’s best to switch modes or open the windows for ventilation every half hour to protect your health and enhance comfort.

[PeterAnn]

I prefer using the recirculation mode throughout winter to maintain stable warmth inside the car, preventing cold drafts from outside and making seat heating more effective. However, if I accidentally leave it on too long and the windows suddenly fog up, I quickly switch to fresh air mode for a few seconds to let dry air clear the mist and avoid accidents. In heavily polluted urban areas, I never use fresh air mode to avoid inhaling exhaust fumes and dust; when driving through parks or mountainous areas, I briefly switch to freshen the air. This combination is simple, practical, reduces AC energy consumption, and is more environmentally friendly.

[Ora]

Using the external air circulation in winter has benefits. It introduces outside air to reduce humidity inside the car, preventing fogging and avoiding the danger of blurred windows. However, using the internal air circulation is more energy-efficient, as it directly heats the interior air, raising the temperature faster, which is especially suitable for short commutes to minimize heat loss. I recommend prioritizing internal circulation for comfort in cold weather and occasionally switching to external circulation for fresh air.

[LeJosephine]

In winter, I prefer to use the air recirculation mode to quickly warm up the car, feeling like being in a greenhouse, especially during long commutes, which saves fuel and reduces noise. However, it's important to note that prolonged use of recirculation can lead to stale air or fogging hazards. Therefore, it's necessary to switch to fresh air mode periodically to release moisture and maintain air circulation, especially on rainy or snowy days or in areas with fresh outdoor air, which can be refreshing. Always prioritize health and safety to avoid carbon monoxide buildup.

[VanAubrey]

My experience is that in early winter, turning on the recirculation mode first when getting in the car heats up faster to avoid shivering from the cold. However, after about 10 minutes, the windows tend to fog up, so I switch to the fresh air mode briefly to introduce outside air and clear the fog. Especially in urban areas with smog, the fresh air mode can purify the cabin air, but it's important to quickly switch back to maintain a comfortable temperature and avoid catching a cold, making driving more reassuring. Remember, in cold weather when the air is dry, alternating between these modes can extend the lifespan of the air conditioning system.