Lately, you’ve noticed that your beloved AC hasn’t been humming like it used to.  You may have even noticed that it’s making strange noises.  You may even be asking yourself, “Why is my AC so loud?”  Thankfully, we know why it’s noisy and how to prevent and fix these issues.  Let’s start by figuring out what types of noises your air conditioner is making. Then we can find out if an air conditioning repair is needed or not.

Types of noises

Listen closely to your air conditioner when it turns on, while it’s operating, and as it shuts off.  Do you hear a buzzing sound?  Is it rattling?  These different noises mean different potential issues, so it’s important to get an idea of what sounds you’re hearing.


If you hear a buzzing sound, you may have an electrical issue.  The sound is generally a sign of electrical arcing, which is the electrical discharge that is visible when electric currents jump between different circuitry in the system.  It may also be caused by a burned contractor or bad connection.  This may be caused by wear and tear of the system over its lifespan.


A clicking noise may be caused by a faulty thermostat turning on and off because of relays being tripped. The clicking may also be caused by a damaged fan blade or an obstruction within the area of the blade.


If you notice rattling noises coming from your outside unit, it may be caused by objects that have fallen into the vents (sticks, leaves, dirt, etc.).  It may also be the sound of loose parts rattling against each other while your air conditioner is running (loose screws, bolts, etc.).  On the other hand, you may have an issue with your compressor.  The motor within the compressor may begin to make noises and get louder with age, and may be taken as a warning sign for bigger problems in the near future.


Popping  sounds may be heard when your air conditioner turns on and off.  The noise that you’re hearing may actually be coming from your ductwork, not your AC unit.  With regular maintenance, you can help to avoid the popping noise and keep your ducts in working condition.


A grinding noise may be caused by a couple of different issues.  The noise may be coming from your compressor, which is most likely the result of aging or heavy use.  Worn out pistons and other loose or broken components in the compressor may be causing the grinding noise.  Another possibility is a fan motor issue, which may be caused by wear and tear such as a worn out bearing.

Air Conditioning Repair

Whistling or Hissing

If you hear a whistling or hissing sound, you may have an issue with your ductwork.  If you hear a hissing noise coming from your AC unit, you may have leaky refrigerant lines.

Loud Bang

A loud bang noise that happens when your AC turns off may be caused by a couple of different reasons.  If you hear the noise coming from inside your home, it may be ductwork related.  The popping happens because the ductwork may flex when the air is on, and then pop back into place when the system shuts off. If the sound came from outside, it may be caused by a broken or damaged mount that allows the compressor motor to move upon being turned on.

Let Us Help

If you are hearing any of these unpleasant sounds coming from your AC system, please contact us right away.  Though some of the noises may be not big signaling huge problems now, they are simply warning signs for bigger problems to come.


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