Should the internal circulation be turned on when using AC in summer?
4 Answers
When turning on the AC in summer, it is generally recommended to activate the internal circulation mode. Here are the specific details about the car's internal circulation function: 1. Internal circulation button: The internal and external circulation buttons may be separate or combined on a single button. When the indicator light is illuminated, it indicates the internal circulation mode is active. If the buttons are combined, the internal circulation is engaged when the light is on, and external circulation is active when the light is off. 2. Function of internal circulation: The internal circulation mode prevents outside air from entering the vehicle. It is advisable to use this mode when the outside temperature is extremely high or low, as it allows the AC system to quickly cool or heat the cabin. If the vehicle is equipped with an air quality sensor, the system will automatically switch to internal circulation when it detects high concentrations of harmful substances in the outside air, preventing them from entering the cabin. Once the outside air quality returns to normal levels, the system will automatically deactivate the internal circulation mode, allowing fresh air to enter the vehicle again.
Using the recirculation mode when turning on the AC in summer is a smart move, for obvious reasons. Having driven for over a decade, I always activate recirculation first thing on hot days—it significantly boosts cooling efficiency by only chilling the existing cabin air rather than pulling in scorching outside heat. This makes the interior cool down much faster, especially during those first critical minutes after entering a sweltering car. But remember, don't leave it on permanently. Continuous recirculation leads to stagnant air with rising CO₂ levels, which can cause dizziness or nausea, particularly during long drives. Once comfortably cooled, switch to fresh-air intake or auto mode to maintain oxygen levels. Pro tip: In humid climates, recirculation minimizes moisture ingress, but monitor windshield fogging when AC dehumidification is active. Vehicles with automatic climate control handle this intelligently—I've verified the system's smart recirculation cycling actually improves fuel efficiency. Ultimately, recirculation is your secret weapon for rapid cooldowns, but strategic ventilation is key to balancing comfort and air quality.
After years of commuting by car, I've developed the habit of using the air recirculation mode in summer to quickly cool down my car. The principle is that recirculation blocks external hot air, allowing the AC to only process heat exchange within the cabin. This reduces compressor workload and saves fuel. For example, in 40°C heat, recirculation cools the car in minutes - much faster than fresh air mode. But as a family driver, I advise against prolonged use as poor air quality in enclosed spaces can cause fatigue or headaches. Especially with elderly or children onboard, switch to fresh air after cooling, or use it on highways for safety. Modern automatic AC systems are smart - most cars automatically adjust recirculation ratio when you press AUTO, balancing based on temperature/humidity changes. Proper recirculation use enhances comfort while extending AC lifespan and reducing maintenance issues.
In summer, it's best to turn on the air recirculation mode when using the AC, as it speeds up the cooling process. I understand that this mode only circulates the air inside the car, reducing the workload of processing external heat, making it noticeably more efficient and less taxing. However, avoid keeping it on for too long to prevent stale air and window fogging. Vehicles with automatic AC systems can handle the switching automatically, making it even more convenient.
