Should the Car Air Conditioner Use Internal or External Circulation in Summer?
2 Answers
First turn on the external circulation or open the windows for ventilation, then switch to internal circulation. Here are the relevant details: 1. In the hot summer, many car owners habitually turn on the internal circulation of the air conditioner as soon as they get into the car, thinking that this will cool down the cabin temperature faster. 2. External circulation actually sends air from outside the vehicle into the cabin through the air filter element and blower, while internal circulation simply blocks the external air intake flap. 3. Whether it's internal or external circulation, exhaust gases inside the car will be expelled through the vents, so even with internal circulation on, there's no need to worry about the oxygen levels in the cabin air. Additionally, when the outside air quality is poor, it's necessary to turn off the external circulation and promptly use internal circulation to prevent harmful gases from entering the cabin. When internal circulation is on, one should not assume the car is airtight. Although internal circulation prevents outside air from entering the cabin, exhaust gases inside the vehicle will still be expelled through the vents.
I've been driving for almost twenty years, and there's a lot to know about using the air conditioning in summer. When it's extremely hot, turn on the recirculation mode immediately after starting the car. This helps retain the cold air inside quickly and prevents hot outside air from entering, significantly improving cooling efficiency. However, never keep the recirculation mode on for too long, as it restricts airflow, leading to a buildup of carbon dioxide inside the car, which can cause drowsiness or even dizziness. Usually, after five or six minutes when the car has cooled down, switch to fresh air mode to introduce outside air, ensuring smooth breathing and preventing window fogging that could obstruct visibility. I also recommend regularly cleaning the air conditioning filter, as summer dust can easily clog it, reducing cooling efficiency. Lastly, remember not to set the temperature too low—around 25°C is comfortable and saves fuel.
