Why Is My AC Making Noise? Five AC Sounds and What They Mean

As the hot weather amps up, there’s one sound that’s a constant: the air conditioner. By the end of summer, the sound of the AC becomes almost background noise, so familiar we sometimes feel strange without it. Everything is well and good until you start to hear a strange sound coming from the very unit designed to keep you cool. Keep in mind, when you first start your AC, after a season of it laying dormant, a few sounds are natural. It could be the AC clearing dust or small debris, or just the system coming to life again. But when you hear a banging, rattling, or popping, it might be time to call an HVAC expert at Bell Brothers. If you ever find yourself wondering, “why is my ac making noise?” We’re sharing the five most common AC sounds and what they mean.

#1 Screaming or Screeching

If you hear something related to a mechanical screech or wail coming from your system, it should be investigated immediately. If you hear the screaming coming from your outside unit, it could be two things;     the fan motor or the compressor. The fan motor will make a screaming sound if the bearings      around the motor are stripped or shot. This is an easy fix for one of our skilled HVAC techs. The other issue with your outside unit could be the compressor. If your compressor is making a screeching noise, you may need to replace the whole system. Also, if your compressor is under too much pressure, it could let off a loud      scream. If this is the case, turn off your AC immediately and schedule someone to come look at it.

#2 Banging

Sometimes, a banging or slamming noise can come from your AC unit. This sound could be a few things, all ranging from not a big deal to very big deal. Sometimes, the fan can come a little loose and start banging. If this is the case, all you need to do is have one of our skilled HVAC technicians tighten the fan. We don’t recommend doing this yourself because to access your condenser’s fan, first you must bypass electric work that could be hazardous to someone who is not trained in HVAC. Another common reason for banging could be that a stick, or some other debris is in the way of the fan. Banging could also be from a loose part. This could be minor, or it could require a major fix; either way, it’s best to schedule service with our HVAC professionals.

#3 Clicking

If you hear a clicking noise coming from your AC unit, it could be an indicator of a few different problems. This AC sound could be fan obstruction. As we mentioned in our banging section, a branch or another type of debris can get in the way of your condenser’s fan, causing a clicking noise. If you hear constant clicking and the AC won’t turn on, this could be attributed to an electrical problem. Either the thermostat has some frayed wiring, or the control board switch has stopped functioning—no matter what, it’s time to call Bell Brothers.

#4 Humming

Fortunately, if a humming noise is coming from your AC, it’s usually not a huge concern. Though we say this, don’t take it as a free pass to not schedule an appointment. A buzzing noise could be from loose parts or faulty refrigerant piping. The buzzing just indicates the problems haven’t escalated yet. Buzzing could also be a warning sign of electrical problems. The good news, we say keep running your AC if you hear a buzz, just be sure to call a certified HVAC technician to check everything out, especially if the noise gets worse.

#5 Squealing

We all know the squealing noise, it’s similar to the sound a loose belt in your car’s motor would make. If you hear this noise coming from your AC unit, it could probably be one of two things. First, the bearings on your condenser may need to be replaced. As we mentioned in the screaming section, bearings can come loose or just wear out over time. Loose or worn bearings can cause a screaming or squealing noise. The other reason for a squealing AC could be the belt that connects the blower to the motor. Just like in a car, if this belt is old, worn, or warped, it will cause a squealing noise until it settles.

Is Your AC Making Noise? Call Bell Brothers Today

At Bell Brothers, we pride ourselves on keeping your air conditioner in tip top shape. We are open and ready to safely serve our Sacramento, Stockton, and Vacaville communities. Bell Brothers is also more than HVAC; we offer expert plumbing, window replacement, water heater, and home insulation services. All of our technicians have a wide range of skills, are knowledgeable of the home service industry, and practice exceptional customer service.

Ready to schedule services with us? Just call the number at the top of the screen or click here to request an appointment online. One of our friendly Bell Brothers representatives will be with you shortly!