Is it better to use internal or external air circulation when turning on the car's air conditioning?
3 Answers
Both internal and external air circulation can be used when turning on the car's air conditioning, as there are no strict requirements. A better practice is to alternate between internal and external air circulation. Internal circulation is mostly used during traffic jams, as it can isolate the outside air and prevent polluted air from entering the car. External circulation is mostly used during long drives, as it allows fresh air from outside to enter the car. Internal circulation means that the air blown by the blower only circulates inside the car. Since no external air is involved, it has the advantages of saving fuel and providing faster cooling or heating, but the disadvantage is that it is not conducive to refreshing the air inside the car. External circulation means that the blower draws air from outside the car and blows it into the car. The advantage is that it maintains the freshness of the air inside the car, but the cooling or heating speed is slower.
When driving, especially in summer with the air conditioning on, I mostly prefer using the recirculation mode. This allows the cool air inside the car to circulate quickly, cooling down the temperature rapidly, particularly when the outside temperature is as hot as a steamer. If the fresh air mode is used, the hot air from outside keeps coming in, forcing the air conditioning to work harder and resulting in slower cooling. However, don't just focus on staying cool—prolonged use can make the air stuffy, like being trapped in a plastic bag, leading to foggy windows or drowsiness. So my trick is: turn on recirculation mode initially for rapid cooling, then switch to fresh air mode occasionally for a few minutes once the interior temperature stabilizes. This maintains fresh air while preventing window fogging. Adopting this habit has made driving much more comfortable, saving energy and extending the air conditioning's lifespan. If the outside air quality is poor, like during heavy traffic with lots of exhaust fumes, recirculation mode also helps block pollution.
As a young person who drives frequently, I absolutely love using the recirculation mode to blow cold air. Just imagine the feeling: on a scorching summer day, with the AC set to recirculation mode, the cold air rushes in and cools you down instantly—it's like turning your car into a little igloo, super efficient. If you use the fresh air mode instead, the hot air from outside creeps in, making the cooling process sluggish. It's not just about comfort; using recirculation is also more fuel-efficient and puts less strain on the AC system. However, keeping it on recirculation for too long can make the air damp or a bit stale, especially during long drives. I often find myself switching to fresh air mode every half hour while listening to music or chatting, just to let some fresh air in without losing the coolness. Also, don’t forget—if it’s raining or fogging up on a downhill slope, fresh air mode can actually be more useful. So, the key is to switch flexibly and not let recirculation turn your car into a stuffy can.
