What Causes Odor in Car Air Conditioning?
3 Answers
There are several reasons for odor in car air conditioning, including evaporator and air filter issues. Below are the specific causes: Evaporator: The evaporator is a key component in air conditioning cooling. During the cooling process, it comes into contact with external air. In large cities or industrial areas where the air is more polluted, it is prone to drawing in dirt and dust into the air conditioning circulation system, which can easily cause odors. Air Filter: The main function of the air filter is to filter the air. After prolonged use, it can accumulate dirt and dust. If not cleaned or replaced for a long time, it is likely to produce odors.
As a seasoned road-tripper, I've encountered the issue of foul AC odors multiple times. I remember last summer during a long drive when I suddenly smelled a sour, musty odor. Upon inspection, I found the AC system was teeming with mold. The evaporator had become like a miniature swamp - the condensation from AC cooling mixed with dust, creating an ideal breeding ground for bacteria. I later took it to a repair shop for a deep clean where the mechanic steam-cleaned the evaporator with high-pressure steam and replaced the activated carbon filter. Now I always turn off the AC five minutes before shutting down the engine to let the fan dry out residual moisture. I recommend getting an AC sterilization before every summer, especially in humid southern regions, otherwise the air blowing out could be worse than smog.
For us long-distance highway drivers, the most dreaded thing is foul odors from the air conditioning. The other day when I was driving friends, a pungent musty smell hit us as soon as I turned on the AC, making everyone cover their noses. After researching, I learned the root cause lies in the cabin air filter: ordinary filters get clogged with dust and leaves within three months, becoming a breeding ground for bacteria in humid conditions. I switched to a dual-function bamboo charcoal filter and noticed much fresher air. Additionally, the corners of air ducts are prime spots for grime buildup, so I spray disinfectant into the vents monthly. When using fresh air mode, it's best to avoid chemical plants or landfills, as harmful gases can directly enter the car and are harder to eliminate. Keeping a car air purifier also helps absorb unpleasant odors.
