Should the internal circulation be turned on when using AC in summer?

[DelArthur]

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.