What does it mean when your AC grinds, hisses or squeals?

It’s normal to hear sound coming from your air conditioning unit. It’s probably most noticeable when it turns on. But while some types of noises and level of noise is common from an air conditioner, do you think you are hearing something that might not be normal?

Irregular sounds from any part of a heating or cooling system is often the first sign of trouble. You should not ignore any sound you think is odd or different than usual.

Air Conditioner Making Weird Noises: Diagnosing Problem Sounds

AC Making odd noises diagnosis for hissing, buzzing, squealing, and clankingWe often refer to the normal sound air conditioners make as a hum. But it’s definitely going to be louder than a person humming.

Your outdoor unit, called the condenser, can be expected to be loud enough to be heard when you’re outside or in a room not far from where it’s located. Most AC units operate with sounds that can be as loud as 70-80 decibels. That’s about as loud as a dishwasher running or hearing light traffic.

If you’re reading this, chances are you’re hearing something different than you’re used to. That might not be a problem, but it’s something you do need to look into. You will want to listen closely and identify what type of sound it is making. Depending on the sound, any number or problems could be happening with some part of your air conditioning system.

At Standard Plumbing, Heating & Air Conditioning, we’ve received calls from homeowners who’ve described a wide variety of different odd sounds their AC is making. Our team knows what each sound could mean and can address and fix whatever the problem is, no matter what type or make of system it is.

Metallic or Grinding Noise

If your AC is making a noise that sounds like metal is grinding together, that definitely is not normal and does indicate there is some sort of problem.

Possible problem #1: It’s very likely you have a problem with your compressor. Specifically what you could be hearing are the pistons in your compressor not working properly.

Possible problem #2: The blower fan belts are loose or damaged. That noise could be the sound of the fan belt rubbing up against other AC components.

Solution: Call a professional. If the problem is a fan belt, that is not easy to repair on your own. However, depending on how quickly you caught and responded to the problem, it might be a relatively easy repair for an HVAC technician to handle. If the issue is the compressor, it may need to be completely replaced. Having a professional technician look at your system will ensure that the right problem is diagnosed and properly addressed.

Hissing or Screaming

If you hear what sounds like a hissing noise or even something like screaming, you do not want to delay getting it addressed.

Possible problem #1: These sounds could indicate something as dangerous as a refrigerant leak. Refrigerant leaks aren’t just potential dangers to your health, but they can cause further problems in your cooling system. A leak left unaddressed could damage AC valves.

Possible problem #2: A hissing or screaming sound could mean your compression pressure is too high.

Solution: First, turn off your AC. Since the problem could be a hazard to your home and family, you should shut off your cooling system if you hear hissing coming from it. Then, call a professional right away to thoroughly and safely handle whatever issue is causing this sound. Call Standard for service in the Manhattan, KS area at (785) 776-5012.

Squealing AC

Are you hearing a high-pitched squealing sound?

Possible problem #1: Do you have an older AC unit? If so, this sound likely indicates a problem with your air conditioner’s motor fan. The belt on your motor fan may have slipped. Newer air conditioners do not use a belt system.

Possible problem #2: This sound could mean there is a problem with the bearings on the AC motor fan. This may be the case if you have a new AC that does not have a belt.

Solution: If you have sufficient home repair skills, you can attempt necessary maintenance to tighten up and/or readjust any components that may be loose or out of balance. But your best bet would be calling a professional technician to adequately diagnose and fix any and all problems.

Buzzing Air Conditioner

If your AC is buzzing instead of just humming, that means you need to look into potential problems. Many different issues could be causing your AC to buzz.

Outside AC unit compressorPossible problem #1: Your AC system has some components that are malfunctioning. The issue could be something as minor as loose parts or damaged feet on your outdoor compressor. The fan blades could simply be loose or out of balance.

Possible problem #2: A buzzing sound could also mean big AC issues. You could be dealing with such serious problems as a refrigerant leak or a broken compressor.

Possible problem #3: You could have an electrical issue.

Possible problem #4: You could simply have a dirty air filter.

Solution: First, make sure to change your air filter if it’s dirty or clogged. If that doesn’t resolve the buzzing sound, and you can easily identify a loose part or a missing or damaged foot, you can try to fix that yourself. But if that doesn’t stop the buzzing sound, call a professional. A trained HVAC repair technician, like those on our team at Standard Plumbing, Heating & Air Conditioning, will have the tools and skills to identify the problem and get it fixed.

Banging, Clanking or Rattling

Possible problem #1: Does it sound like something is banging around? Parts inside your air conditioner can become loose or break off and create a banging noise.

Possible problem #2: Your compressor may need to be replaced.

Solution: If you can spot the loose part and tighten it yourself safely, you may be able to fix the problem. But if that doesn’t stop the banging, call in a professional right away. A loose part can create a lot of havoc on your system and start damaging more components if not fixed soon.

Any Weird AC Sound

Different or unusual sounds coming from your air conditioner are important to notice and address. These are clear signs that something is wrong with your air conditioner. It’s always a safe bet to immediately turn off your air conditioning system once you hear concerning sounds. While some reasons for these sounds could be minor and easy fixes, others are more problematic and even potentially dangerous to your family. In either case, whatever the problem is will likely cause even further problems or damage if you don’t act to get it fixed quickly.

If you are in need of professional AC repair service because you have an air conditioner making weird noises, you can be thankful that your system only needs a repair instead of a more expensive full system replacement. You can have peace of mind knowing that an AC repair from a trained technician will not only fix the problem but also ensure no other looming problems exist. You can expect to have your air conditioner back to proper working order and last for many years to come.

Standard Plumbing, Heating & Air technician doing diagnostic testing on an outside air conditioner

When Air Conditioning Repair Saves You Money

A good AC repair might even save you money in the long run. With your cooling system working as it should, you may even notice energy bills going down. When your AC is malfunctioning, that often means it’s working harder to keep you cool. Having it properly fixed, adjusted and cleaned will allow your system to work at peak efficiency. Plus, by getting the repairs done right away you have likely avoided, or at least put off, more expensive repairs or even an entire cooling system replacement.

What if My AC is Not Worth Repairing?

While not likely, you may be dealing with a problem that means your air conditioner is beyond repair. But more often than that, you could find out that the necessary repair you need really isn’t worth it.

Reason to not get your air conditioning system repaired include:

    If your repair is quite expensive and this isn’t the first fix your AC has needed recently, it may be time to consider getting it replaced. Repair costs add up, and that money would be better spent invested in a more efficient system.
    Even if this is the first time it’s ever needed a repair, if your AC is at least 10 years old, it’s likely on its last legs. You could be facing more repairs or even suddenly finding that it stops working completely.
    You might be dealing with a cooling system that is too old, dysfunctional or even the wrong size unit for your home. There are several reasons why an air conditioner may be using up a large amount of energy to properly cool your entire home. If so, this may be a good time to choose to invest into a new system that will lower your monthly bills and help the environment with reduced energy consumption.

Photo of Standard Heating & Air service van outside Manhattan shopYou need to make sure you work with a professional and qualified heating and cooling company to ensure you get a repair that fully addresses the existing problem as well as look (and resolve) and other potential issues. Standard Plumbing, Heating & Air Conditioning has been providing quality, professional air conditioning repair service for nearly 100 years. Located in Manhattan, KS we are licensed to provide service to residents and businesses in the surrounding towns including Wamego and Junction City.