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From Buzzing to Banging: Understanding the Noises Your AC Makes and What They Mean

April 30, 2024

The first modern air conditioning system emerged more than a century ago. This cooling system worked effectively, but it also generated lots of noise.

Over time, air conditioner manufacturers worked on quieting AC systems down. The average AC unit only generates about 30 decibels today because of this.

However, there may be times when the HVAC system in your home is noisier than usual. Listen to what it’s trying to tell you to determine whether or not something might be wrong.

Find out more about the noises that AC systems make and discover what they might mean.

Identifying Common AC Noises

Under normal circumstances, the AC system in your home should give you the ability to perform climate control without producing too much noise. After it has been running for a few minutes, the noise it makes should blend into the background and go unnoticed.

The only time you’ll need to worry is when you hear your home’s AC system make noises that are out of the ordinary. Here are several noises that should cause you to raise an eyebrow:

  • Buzzing or humming
  • Rattling or banging
  • Clicking
  • Hissing
  • Squealing or grinding

These are the kinds of sounds you won’t want to hear your AC system make. They may indicate a need for AC repairs.

Understanding the Causes of AC Noises

If you ever hear your home’s AC system making any sounds, you may begin to panic. The good news is that these sounds might tell you exactly what’s wrong with your system.

Next, let’s take a look at what each of the common AC noises can mean.

Why Is My AC Buzzing or Humming?

If you ever find that your AC system is making a buzzing or humming noise, there could be any number of things causing it. Some problems that can lead to an AC system buzzing or humming are:

  • Loose or worn-out parts
  • Electrical issues
  • Debris stuck in the outdoor portion of the system

Simply replacing a part in your AC system or cleaning up the outside of it can work wonders for this particular problem. However, since several issues can cause buzzing or humming, you may need to call in the pros to diagnose the problem.

Why Is My AC Rattling or Banging?

If you hear a rattling or banging noise when you fire up your home’s AC system, it may alarm you. This is one of the loudest sounds that can come from a cooling system.

In this case, you might have one of these problems on your hands:

  • Loose fan blade
  • Loose motor mount
  • Debris trapped in the system

You may not be able to ignore rattling or banging noises emanating from your air conditioner for long. Seek assistance from a licensed HVAC technician who can diagnose the issue and correct it.

Why Is My AC Clicking?

If you have a clicking noise coming from your home’s AC system, it’s often a surefire sign there is an electrical problem. An electrical relay within your system may have failed.

Clicking sounds coming from an AC system can also suggest something might be wrong with its capacitor. A capacitor is responsible for sending power to an AC system’s motor, so you’ll need to remedy this situation quickly to ensure your AC system continues to start.

Why Is My AC Hissing?

If you hear a hissing sound stemming from your home’s AC system, it might mean you have a refrigerant leak. This is one of the hardest AC noises to hear, but thankfully, it won’t be the only sign that refrigerant may be leaking from your system.

A refrigerant leak in your AC system may also stop your system from cooling your home when you turn it on. If this is happening, get in touch with an HVAC system repair company right away to schedule an inspection and repair.

Why Is My AC Squealing or Grinding?

If your home’s AC system is squealing or grinding, it can be almost as annoying as hearing it rattling or banging. You might find it impossible to relax at home with your AC system making this much noise.

A squealing or grinding sound coming from your AC system can mean:

  • Broken or loose belt
  • Misaligned pulley
  • Worn-out motor bearing

Don’t delay calling an AC system repair service to assist you. The squealing and grinding you’re hearing might only get worse if you don’t do anything about it.

When To Take Action and Address AC Noises

Springing into action immediately when you hear your home’s AC system making strange sounds can help you mitigate the problem before it worsens. Check out the steps you should take as soon as you hear them:

  1. Investigate the potential sources of your AC noises.
  2. Consider shutting off your AC system to avoid further issues.
  3. Get in touch with an AC repair company and schedule an appointment.

Ignoring AC noises and putting off necessary repairs can cause further damage to your system and possibly even necessitate expensive AC repairs down the line.

The Importance of Seeking a Professional Diagnosis and Repair for a Noisy AC

After hearing what can cause certain AC noises, you may mull over taking the DIY approach to making AC repairs. These are the dangers that can come along with doing this:

  • Additional damage done to your AC system
  • Reduced efficiency from your AC system
  • Premature AC system failure

Instead, allow an experienced HVAC technician to work on your AC system. They can identify why your AC system is making sounds and come up with a solution to fix it.

Let Us Look at Your Home’s Noisy AC System

When you live in your home long enough, you’ll eventually hear sounds you don’t recognize coming from your AC system. Knowing what could be causing them can help you identify what might be the problem with it.

Chud Cooling & Heating can step in and tackle AC repairs if the sounds you’re hearing indicate an issue. Touch base with us at 215-659-4343 to make an appointment in Abington, PA.

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