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

[SanCarmen]

Car AC and internal circulation should not be turned on together. Here are the relevant explanations: 1. External circulation: External circulation refers to drawing air from outside the car, directing it to the air conditioning system for heating or cooling, and then blowing it out through the vents. External circulation can replenish fresh air and improve the air quality inside the car. 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. 2. Internal circulation: Internal circulation refers to the circulation of air inside the car. The air conditioning system draws in the air from inside the car, cools it, and then feeds it back into the car. When the temperature inside the car drops to the set value, the air conditioning compressor will stop working, reducing the load on the engine. Therefore, the faster the temperature inside the car drops to the set value, the sooner the engine load will be reduced, leading to a decrease in fuel consumption.