Should the car use internal or external air circulation when turning on the air conditioning?
2 Answers
When turning on the air conditioning in a car, it is generally recommended to use the internal air circulation. Here is a detailed introduction to the internal and external air circulation in cars: 1. External air circulation: External air circulation refers to drawing air from outside the car, directing it into the air conditioning system for heating or cooling, and then blowing it out through the vents. Essentially, external circulation replenishes fresh air to improve the air quality inside the car. It is used in situations like defrosting in winter or defogging in summer because the air drawn from outside has higher oxygen content and is drier, making it more effective for defrosting or defogging. 2. Internal air circulation: Internal air circulation draws air from inside the car, creating a cycle of airflow within the vehicle. The main purpose of internal circulation is to promptly and effectively prevent external dust and harmful gases from entering the car. It helps the car warm up faster in winter and cool down faster when the air conditioning is on in summer. It can also be used during smoggy days. Internal circulation means the air inside the car is recirculated, which helps maintain the interior temperature more effectively.
In my daily driving, I flexibly switch between recirculation and fresh air modes when using the AC. I always start with recirculation first, as it quickly removes hot air from the cabin and cools down faster with cold air, achieving rapid cooling without opening windows. After about 3-5 minutes, I switch to fresh air mode to allow outside air in for ventilation, preventing stuffiness or odors inside the car. Using recirculation continuously without airflow can lead to CO2 buildup, causing dizziness and fogging. In urban traffic or high-pollution areas, I use recirculation more to block exhaust fumes; on open roads like highways, I switch to fresh air for better ventilation. Additionally, regular cleaning of the cabin air filter ensures fresher air and a more comfortable summer driving experience. This switching method is both practical and simple, becoming second nature once you're used to it.
