Can the car AC and internal circulation be turned on together?
3 Answers
Car AC and internal circulation should not be turned on together. Here are the relevant explanations: 1. External circulation: External circulation refers to drawing air from outside the car, directing it to the air conditioning system for heating or cooling, and then blowing it out through the vents. External circulation can replenish fresh air and improve the air quality inside the car. However, if the weather outside is extremely dry and hot, turning on external circulation will require the air conditioning compressor to work continuously to cool the hot air from outside, which will consume a certain amount of fuel. 2. Internal circulation: Internal circulation refers to the circulation of air inside the car. The air conditioning system draws in the air from inside the car, cools it, and then feeds it back into the car. When the temperature inside the car drops to the set value, the air conditioning compressor will stop working, reducing the load on the engine. Therefore, the faster the temperature inside the car drops to the set value, the sooner the engine load will be reduced, leading to a decrease in fuel consumption.
After driving for over a decade, I've found that using the AC and recirculation mode together significantly boosts cooling efficiency in summer. When I first got my car, I didn't understand this either, but later discovered during long-distance drives that this combination saves fuel remarkably well—especially in scorching weather, as recirculation cools the cabin quickly while blocking hot air from entering. However, watch out for windshield fogging; that's when you need to switch to fresh air mode for ventilation. Always activate recirculation in heavy traffic or polluted areas to prevent exhaust fumes from entering, but remember not to keep it on continuously—switch to fresh air every half hour to avoid excessive CO₂ buildup, which can cause dizziness. My long-haul driving experience confirms that smart toggling between modes improves AC efficiency and saves a good amount on fuel costs.
Recently, while researching car air conditioning, I discovered that both modes can be used simultaneously—a quite user-friendly design. The recirculation mode essentially creates a closed-loop air cycle inside the cabin, which works more efficiently with AC cooling, especially for rapid cabin temperature drop after summer heat exposure. However, air quality must be monitored. Living in a northern city with frequent smog, I’ve found recirculation effectively blocks PM2.5, though prolonged use in humid climates may cause window fogging. Practical tests show that during long highway drives with lower AC load, switching to fresh air mode improves comfort. In winter, I rarely use recirculation for heating since engine warmth suffices, avoiding unnecessary compressor strain.
