Air conditioning units today blend sound dampening technology and variable speed compressors to maintain ambient noise levels at around 55 decibels. So when you hear odd sounds, you should investigate why before it turns into a serious problem.
Why Is My AC Making a Loud Noise?
There are a few distinct noises that your AC unit might make and each noise points to a different problem. Let’s do a quick breakdown of what the different sounds mean.
Screeching or Squealing Noise
A loud screeching or squealing sound, like metal grinding on metal, can be caused by three things. It could be a bad compressor motor, a faulty outdoor fan motor, or a faulty blower fan.
The blower fan could have unlubricated bearings or a worn-out fan belt.
The clicking noise in your air conditioner could be as simple as a small object being stuck in your blower fan. However, hearing the clicking noise when you try to switch on the unit (but it fails to start) is most likely an electrical problem.
This noise is another symptom of faulty electricals. There are several common electrical issues such as loose wiring, broken capacitor, failing motor, malfunctioning compressor, and arcing.
Shaking, Rattling, or Banging Noise
If your air conditioner unit is making a weird noise that reminds you of a poltergeist, the shaking and banging are probably from loose parts. The ducts and motors get subjected to plenty of movement, which over time can loosen component parts.
A loose piston pin, crankshaft, or other parts in your compressor could also be the culprit. Unfortunately, a faulty compressor is one of those parts that most likely need an overhaul by a professional.
Whether the cause of rattling is as benign as loose AC panels or mounting screws, it’s best not to whip out your screwdriver. Call in a trained HVAC professional to avoid putting yourself at risk.
This particular sound is most commonly caused by refrigerant leaking out at high pressure. Over time the thin copper coils which carry the refrigerant can corrode, especially when not cleaned regularly. Nipping such issues in the bud is the reason why you should have scheduled maintenance every year regardless of how beautiful your AC unit sounds.