Should the Car's Air Conditioning Use Internal or External Circulation?
2 Answers
Whether to use internal or external circulation in a car's air conditioning system cannot be generalized and should be determined based on the specific situation. The choice between internal and external circulation should be adjusted according to actual conditions. Below is a detailed explanation of both modes: 1. Internal Circulation: Prolonged use of internal circulation can lead to a decline in air quality inside the car because no fresh air is being introduced. However, when the air conditioning is first turned on, internal circulation can cool the interior temperature more quickly. Using internal circulation during summer for cooling is more energy-efficient. However, prolonged use of internal circulation is not advisable, and it's recommended to occasionally open the windows to let in fresh air before closing them and continuing with internal circulation. 2. External Circulation: External circulation continuously brings in fresh air, but in situations like city traffic jams, it may draw in more exhaust fumes. It is advisable to use external circulation more often when heating the car in winter.
I always encounter air conditioning issues when driving to work on hot days. I found that turning on the recirculation mode (where the air inside the car circulates itself) first when using the AC helps cool down the temperature quickly and prevents hot outside air from making the car even hotter. Once the temperature stabilizes and becomes comfortable, I switch to the fresh air mode to let in outside air, preventing the car from feeling stuffy. Prolonged use of recirculation can make people feel dizzy and sluggish—I once forgot to switch on the highway and almost dozed off, which was quite dangerous. In areas with heavy pollution during parking or traffic jams, I use recirculation to block out odors. Simply put, start with recirculation, switch to fresh air once stable, and drive with peace of mind.
