Is it better to use internal or external air circulation in summer?

[LeBrooklyn]

In summer, it is better to use the internal air circulation mode. When the ambient temperature is very high, using the external air circulation mode with the car air conditioning can lead to significant loss of cooling capacity, resulting in higher fuel consumption and increased fluctuations. Most of the time, internal circulation should be used. When the air quality inside the car is poor and the external temperature is not too high, external circulation can be appropriately used to improve the air quality inside the car. Using internal circulation when cooling with the air conditioning in summer is obviously more energy-efficient, but prolonged use of internal circulation is not ideal either. It is advisable to open the windows occasionally to let in fresh air and then close them to continue with internal circulation. Generally, it is recommended to start with external circulation to expel hot air, then switch to internal circulation after a while for better cooling effect.

[DiWillow]

Using the air conditioning in summer, I find the recirculation mode particularly practical. Just think about it, under the scorching sun, the outside air is as hot as an oven. When you turn on the recirculation mode, the AC draws air directly from inside the car, avoiding the need to cool down that steaming hot fresh air from outside, so the cooling is much faster. I often commute to work, and in the morning, getting into the car feels like stepping into a sauna. I immediately switch to recirculation mode, and within two or three minutes, it cools down quickly, saving both electricity and fuel. If you keep using the fresh air mode, the AC has to work harder to cool down the hot air from outside, which not only consumes more energy but also slows down the cooling inside the car. However, if you use recirculation mode for too long, the air can become stuffy, especially when I have family in the car—they tend to feel dizzy. So, after about half an hour, I usually switch to fresh air mode to let in some fresh air. In short, prioritize recirculation mode for quick cooling in summer, but don’t keep it on all the time. Alternate appropriately to maintain fresh air inside.

[Steph]

The recirculation mode is a real energy-saving expert in summer. I noticed that when using the fresh air mode, the AC has to cool down the hot air drawn from outside first, which consumes a huge amount of energy. In contrast, recirculation keeps the air circulating inside the car, making temperature control easier and reducing the AC's workload, resulting in more economical operation. I once tried it on a long-distance trip – with full-time fresh air mode, the fuel gauge dropped quickly, but switching to recirculation saved significantly more fuel. Plus, the AC doesn't need to work as hard, so it's quieter too. However, when there's heavy smog or dust outside in summer, fresh air mode can actually be risky as it brings pollutants into the car. My suggestion is to use recirculation most of the time for quick cooling and energy savings, but occasionally switch to fresh air mode for ventilation.

[SanMadeline]

I think the recirculation mode is better in summer, but health factors must be considered. For example, recirculation cools the car quickly, but keeping it on for too long can lead to insufficient oxygen, which may cause drowsiness or headaches. Once, I dozed off on the highway and realized it was because I had left the recirculation on for too long. The fresh air mode brings in outside air, preventing the air quality from deteriorating. Therefore, in summer, it's recommended to first use recirculation to cool the car down, then switch to fresh air mode to ventilate, especially when parked or driving at low speeds.

[CamilaFitz]

Using the air conditioning in summer, the recirculation mode is unbeatable in traffic jams. When stuck in traffic with exhaust fumes outside, the recirculation mode blocks odors and dust, allowing the AC to focus on cooling the cabin air, so I can concentrate on driving without worrying about inhaling pollutants. But on highways or at night when the outside breeze is cooler, the fresh air mode is more comfortable as it maintains airflow. In daily city driving during traffic jams, I use recirculation, and switch to fresh air mode when leaving the city.

[Joyce]

In summer, prioritize the internal circulation mode as it cools the car down faster and prevents hot outside air from entering, making the air conditioning more efficient. With children in the car, internal circulation ensures a stable temperature, preventing them from complaining about the heat. However, if the air gets too stuffy, I switch to external circulation every 20 minutes or open the windows for ventilation to avoid dust buildup and unpleasant odors inside the car.