Do you know the most common air conditioner problems?

If your guess includes refrigerant leaks, electrical issues, and drainage problems, you’re correct. The bigger question, though, is—do you know how to diagnose these issues? 

The good news is, even if you’re not an HVAC professional, there’s one obvious sign that will let you know there’s something wrong with your AC—an AC making noise all the time isn’t normal and is always worth a service call. 

Now, if you’re not sure if you should call an air conditioning expert, it helps to know why your unit is making those weird noises. Here, we’ll discuss some air conditioning sounds you might hear and their causes. 

Banging, Clanging, or Knocking

There are two main reasons why your outdoor unit is emitting a loud banging sound. One, your AC’s compressor is faulty and needs replacement—and two, its fan is hitting something. 

If it’s a compressor problem, the bad news is there’s almost nothing a tech can do to fix it. That’s because it would require damaging the outer shell since the compressor is hermetically sealed. Your best bet is to get a new one, which isn’t a problem if it’s covered under your warranty. 

Now, if your unit’s fan has come loose or if there’s something hitting it (a stick or any obstruction that shouldn’t be there), you need to turn off your AC right away. Don’t remove it yourself. Make sure to call an AC expert to take care of the issue. 


If you hear your air conditioner humming, it’s not something you should ignore, especially if your unit’s new.

Remember, newer AC models are quieter than ever, so even a simple humming sound could indicate a problem with your unit.

Common culprits include loose parts, electrical issues, or a faulty motor. If it turns out to be an electrical problem, don’t attempt any DIY repair.

Messing with your unit’s electrical system is very dangerous unless you’re a licensed electrician.

Screaming or Screeching

Even for older ACs, a screaming sound isn’t normal.

In fact, it’s an emergency repair situation, because the most probable cause is a refrigerant leak. 

If it’s not that, then it’s high internal pressure within your unit’s compressor, which is still a potentially hazardous situation.

Again, keep your AC shut off and make sure to schedule an AC service ASAP.

AC Making Noise? Other Sounds to Watch out For

Aside from banging, humming, and screaming noises, you may hear your AC making clicking, buzzing, and chattering sounds.

A good rule of thumb to follow is if your unit’s making a weird noise, have it checked by a professional.

The sooner an expert can look at your AC, the higher your chance of avoiding costly repairs.  

Need AC Service, Repair, or Maintenance?

We can help.

Whether you’re worried about your AC making noise, or some other problem like your unit blowing hot air, we’d love to help you out.

To schedule an AC service, repair, or maintenance, don’t hesitate to contact us.