Should the Car Air Conditioning Be Set to Recirculate for Cooling?

[JuniperFitz]

When using the car air conditioning for cooling, it is recommended to set it to recirculate mode. This is because in recirculation mode, the air conditioning system cools the air inside the car cabin, which is already at a lower temperature, resulting in faster cooling and better efficiency. However, it is not advisable to keep the recirculation mode on for extended periods. Prolonged use can lead to a decrease in oxygen levels inside the cabin, causing drowsiness and discomfort for passengers. It is recommended to switch to fresh air mode intermittently to maintain air quality. Additionally, in areas with severe air pollution, using recirculation mode can help reduce the intake of PM2.5 particles by passengers. Overview: The car air conditioning system (air-conditioning-device), commonly referred to as car AC, is used to regulate and control the temperature, humidity, air cleanliness, and airflow within the car cabin to maintain optimal conditions. Functions: The car air conditioning system provides a comfortable environment for the driver, reducing travel fatigue, and creates favorable working conditions to ensure driving safety. The car air conditioning system typically includes cooling devices, heating devices, and ventilation devices.

[AutumnFitz]

I've been repairing cars for over a decade and seen plenty of AC issues. For cooling, you must use recirculation mode! When there's a heatwave outside, using fresh air mode is like pumping oven-hot air into your car - the AC will struggle endlessly to cool down. Recirculation reuses the chilled cabin air, cooling faster while saving fuel. But remember two things: First, don't keep it on continuously - switch to fresh air every half hour on long trips to prevent dangerous window fogging. Second, when defogging in rain, remember to switch back to fresh air mode, otherwise the fog will just keep building. I've seen too many people stubbornly using recirculation until they get dizzy and lightheaded.

[DeGabriel]

Last time I drove my bestie's new car on the highway, even with the AC at max, I was sweating buckets. Turned out she had it on fresh air mode! Switched to recirculation and it cooled down in five minutes. Now here's my routine: in summer, I open the doors first to let the heat out, start the car, immediately engage recirculation and AC, crank the temp to lowest, then adjust to around 23°C once cooled. Though with passengers or after eating pungent food, I secretly toggle to fresh air mode. The manual actually recommends alternating between modes, but let's be real—who bothers reading manuals?

[CalebLee]

Using the recirculation mode during cooling does provide better results by reducing the entry of external hot and humid air, helping the air conditioning to cool down faster. However, prolonged use can lead to increased carbon dioxide levels inside the vehicle, potentially causing driver fatigue. Therefore, it is recommended to use it continuously for short urban trips; for long-distance driving, switch to fresh air mode for 5 minutes every 30 minutes; if fogging occurs inside the car, immediately switch to fresh air mode and activate the defogging function. Some automatic air conditioning systems in certain models have an intelligent mode that automatically switches between recirculation and fresh air, eliminating the need for manual adjustment.