What Causes the Abnormal Noise When the Car Air Conditioner Starts?
3 Answers
Fault phenomena of abnormal noise when the car air conditioner starts: 1. Air conditioner pump head: This fault mainly involves the engagement surface of the air conditioner electromagnetic clutch. If the electromagnetic clutch is in a worn state, it will cause the aforementioned noise phenomenon. If the fault source is confirmed, it is recommended to replace it. 2. Bearing performance: Bearing performance mainly refers to the compressor clutch bearing. This type of fault source usually occurs when the air conditioner is working and is directly related to acceleration. The sound characteristic is also a "buzzing" noise. Therefore, for the above-mentioned vehicle fault phenomena, it is recommended to go to a repair shop to inspect the above maintenance suggestions.
To be honest, I've driven several cars and have experienced strange noises when the AC starts up, which is mostly caused by a few common reasons. First, it could be an issue with the AC compressor—clicking sounds upon startup might indicate a worn electromagnetic clutch or insufficient lubrication causing abnormal friction in the components. Second, it might be due to loose or aged drive belts, especially in hot summer weather when belts tend to slip and produce squeaking noises—an easily overlooked detail. Another possibility is foreign objects stuck in the fan or blower, such as accumulated leaves or dust, which can cause a loud humming sound at startup. Of course, insufficient or leaking refrigerant can also cause abnormal noises due to pressure changes in the lines, so it's best to get it checked promptly to avoid affecting the entire AC system. I recommend regularly cleaning the AC filter, and if the noise persists, don’t delay—take it to a professional repair shop for diagnosis. Otherwise, if the AC suddenly fails while driving, the heat on the road can be unbearable.
That squeaking noise when you first turn on the AC isn't something to ignore—let me highlight the potential risks. The sound often originates during compressor startup; for instance, if the electromagnetic clutch engages roughly, it'll produce alarming clicking noises that could eventually fry the compressor if left unchecked. Don't overlook the belt system either—a loose or worn belt will screech from slippage during initial engagement, which is unsettling; best inspect the tensioner promptly. Another culprit could be debris lodged in or bent fan blades, causing loud buzzing noises possibly accompanied by vibrations that disrupt driving comfort. My advice: next startup, pinpoint the noise location—if it's from the engine bay, pull over immediately for inspection. Don't wait until the AC fails completely. Safety first—regular maintenance saves headaches.
