Should You Use Internal or External Air Circulation When Running the Car AC?

[EmmaLynn]

Both internal and external air circulation can be used when running the car's AC. There is no strict requirement, but the best practice is to alternate between internal and external circulation. In winter, whether to use internal or external circulation for the heater depends on the situation: 1. To quickly heat up the car interior, use internal circulation. 2. The car interior forms a relatively sealed environment, and prolonged use of internal circulation can lead to oxygen deprivation, so it's best to switch to external circulation every hour. Below are some tips for using the AC in summer: 1. The correct way to use the AC in summer: First, open the windows to ventilate and lower the interior temperature before turning on the AC. Start with internal circulation, then switch to external circulation to maintain fresh air inside the car. 2. Avoid rushing to use internal circulation in summer.