Why does the car air conditioner have a sour smell?

[LeviMarie]

Reasons for the sour smell in car air conditioners: When the car air conditioner is cooling, it lowers the temperature of the air through the evaporator unit. During operation, the temperature of the evaporator can drop to around 0 degrees Celsius, making it function similarly to a refrigerator. The cooled air then enters the cabin. The damp environment inside the evaporator provides an ideal condition for fungal growth, which is the source of the sour smell. The car air conditioning system is designed to cool, heat, ventilate, and purify the air inside the vehicle, providing a comfortable environment for passengers, reducing driver fatigue, and enhancing driving safety. As such, the air conditioning system has become one of the indicators for evaluating whether a car is fully equipped.