Can the car AC and internal circulation be turned on together?

[Billy]

Car AC and internal circulation should not be turned on together. Here is relevant information: External circulation: External circulation refers to drawing air from outside the vehicle, directing it to the air conditioning system for heating or cooling, and then blowing it out through the vents. External circulation can supplement fresh air and improve the air quality inside the vehicle. However, if the weather outside is extremely dry and hot, turning on external circulation will require the air conditioning compressor to work continuously to cool the hot air from outside, which will consume a certain amount of fuel. Internal circulation: Internal circulation refers to the circulation of air inside the vehicle. The air conditioning system draws in the air inside the car, cools it, and then recirculates it back into the cabin. When the interior temperature drops to the set value, the air conditioning compressor will stop working, reducing the engine load. Therefore, the faster the interior temperature drops to the set value, the sooner the engine load is reduced, leading to a decrease in fuel consumption.