automatic air-recirculation system

Definition

Cars & Driving

  • noun a heating and ventilation subsystem which automatically switches to the recirculation mode when the pollutant levels of the air inside the vehicle exceed certain levels (e.g. in rush-hour nose-to-tail traffic), but after a certain period of recirculation (typically after 3 minutes), opens the intake air doors again to let some fresh air in, even if its quality is still questionable
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