What is the difference between the internal circulation and external circulation in a car?
1 Answers
Internal circulation refers to the air inside the car being heated or cooled and then recirculated back into the car, while external circulation refers to drawing air from outside the car, heating or cooling it, and then bringing it into the car, which means exchanging air between the inside and outside of the car. Internal circulation allows the air inside the car to circulate when the car is closed, and the icon typically shows a closed car interior with a circulating arrow. External circulation, on the other hand, brings outside air into the car, and the icon usually shows an open car with an air arrow pointing into the car from the outside. Whether it's heating or cooling, it's best to first turn on internal circulation. Although the temperature inside the car will drop, the carbon dioxide exhaled by passengers will increase. Therefore, it's advisable to switch to external circulation every hour to refresh the air. When turning on the air conditioning for cooling or heating, you can start with internal circulation to quickly lower or raise the temperature inside the car. Once the temperature stabilizes, it's good to switch to external circulation to exchange air with the outside. However, if the outside air quality is poor, such as in heavy traffic with lots of exhaust fumes or in a poorly ventilated underground garage, avoid using external circulation. If you're driving on the highway, do not open the windows—simply turn on external circulation.
