Should the internal circulation be turned off when the car is turned off?

1 Answers
MaximusFitz
07/29/25 3:50pm
It is not necessary to turn off the internal circulation when the car is turned off. Below is more information about the circulation modes: Below is more information about the air conditioning circulation modes: 1. External circulation: External circulation draws air from outside the vehicle, filters it through the air conditioning filter, and delivers it into the cabin via the blower. This mode is used for defrosting in winter or defogging in summer because the air drawn from outside is richer in oxygen and drier, making it more effective for defrosting or defogging. 2. Internal circulation: Internal circulation blocks the air intake vent from the outside, preventing the inside air from escaping. Its main function is to promptly and effectively prevent external dust and harmful gases from entering the cabin. 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.
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