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You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

Is Your AC Unit Talking To You? Here’s What It's Trying To Say




Do you hear a loud noise coming from your AC unit? Anything from a buzzing noise to squealing noise, there are several reasons why your AC could be making unusual sounds. To help you determine where the noises are coming from, we’ve rounded up some of the most common reasons why your AC Unit could be making strange sounds.

You may hear hissing in the night or a clicking noise that just won’t stop. What is cause for alarm and what is normal? Together, let’s go over each noise and what they mean. If any of the noises below sound familiar it could signal an electrical problem, a refrigerant leak, loose parts, and more.

If you’ve got a problem, let’s get your AC unit back to running smoothly and silently. Keep reading to learn why your unit is being so loud and what you can do about it. 

Air Conditioner Noises To Watch For

If your air conditioning system is making a loud noise that doesn't sound like normal operation, it's likely because something is wrong with the moving parts inside the unit. A helicopter like noise, or a whirring sound could be an indicator of a mechanical issue. 

In most cases you will need an AC repair professional to come in and diagnose the cause of the mechanical problem. It’s best not to try and find the mechanical issue yourself if you don’t know what to look for. Mechanical issues aren’t easy to solve on your own.

Here’s a list of sounds to look out for and what they could mean.

A Squealing Sound:

If your air conditioner is making a squealing or grinding noise, it could be because the unit is working harder than normal. This can happen if you have an older model that needs replacing.

If you've had your AC for more than 10 years, it may be time for an upgrade. Newer models are more energy efficient and quieter than older ones. This can make all the difference in how comfortable your home feels during hot weather.

Another possible reason is dirty filters. Dirty filters restrict airflow through the system. A dirty filter will cause extra strain on motors, which results in more noise while they run at full capacity. It may mean extra work for your AC unit and loud squealing. It's recommended to change your air filter every 1-3 months.

To fix squealing from your AC unit, have a professional find the sound. Regular maintenance will keep your unit lasting longer and your filters clean. This also means a healthier home and cleaner air.

A Buzzing Noise:

You may be hearing a buzzing noise coming from your AC unit; this can signal that your thermostat is set too low. Check the settings on your thermostat and make sure they're correct, if they are entirely too low, adjust them accordingly. This will help the buzzing as well as your energy bill

A buzzing noise can also mean your fan isn't running properly.

To troubleshoot this issue, check whether there are any loose wires or any other type of damage near where you plug in your electric cord as this can also cause a buzzing noise.

Your HVAC expert can look at the circuit board inside for signs of damage or corrosion caused by moisture buildup.  

A Rattling Noise:

If you hear a rattling noise when your AC unit is running, there are several things that could be causing it. First, objects could be stuck or there could be a broken fan blade in the fan motor. Broken fan blades will also cause rattling noises in your air conditioning unit.

A bad connection, loose wire, or bad capacitor will also cause rattling sounds. The capacitor is the part that makes electricity.

Rattling is loud and disturbing for everyone in your household. Give your family their peace of mind back and call an HVAC expert to come check out the AC fan.

A Clicking Sound:

A clicking sound may be due to a loose wire in the fan. Clicking also comes from a bad connection somewhere in the circuit. Loose wires are dangerous and need attention from a professional.

Clicking also happens when something comes loose and clicks against another part in the unit. If you hear a constant clicking noise, call an HVAC professional to find the source. 

A Humming Noise:

If you hear humming noises coming from your AC unit, it's likely that the problem is with the compressor or motor. This can be very dangerous if not addressed right away. If you hear this sound, start by calling an HVAC technician.

When the compressor hums and doesn’t start, it could indicate loose wiring or a motor problem. When you have regular maintenance done, this is preventable and it won’t become a more serious issue.

A Banging Noise:

If you hear a banging noise coming from your AC unit, it could be a sign that there is something wrong with the compressor. The compressor is what pumps refrigerant through the system.

The compressor is usually located on top of or near an outside unit and operates by using an electric motor to turn a piston inside of it. The pressure builds up inside of this cylinder when it spins. This forces refrigerant out into other parts of your system where heat exchangers are.

As this process continues over time, bearings within the compressor start wearing out. This eventually causes them not only to become louder but also to cause damage if left untreated. If you're hearing a banging noise, it's best to call an expert right away.

A Whirring Noise:

When your air conditioner starts to make a whirring noise, it could be the result of a fan motor problem. If you notice that the blades are not turning or only moving very slowly, this might indicate that your AC unit is having issues with its fan motor. 

Check the connections and wiring around the fan motor for any loose wires or bad connections. If they're fine and everything looks good, then check to see if there's any damage to any of its blades. You can see if they're turning freely when powered on.

If you’re unsure how to find the source of the whirring noise, call in a professional who knows exactly what to look for.

A Pulsating Noise:

If you hear a pulsating noise coming from your AC unit, it could be caused by a bad capacitor. Capacitors are small components that store energy and release it when needed. If they fail, they can cause the fan to go on and off in short bursts.

If you are not sure if this is what's happening with your system, call an HVAC professional who can inspect the unit. Your technician will determine if your unit needs repairs or replacement parts. A new capacitor or motor assembly will get rid of the pulsating and get your AC unit running again.

A Hissing Noise:

Strange hissing noises coming from your AC unit can be an indicator of a refrigerant leak. An HVAC expert will be able to come check the condenser for a leak. A condenser is the part of your AC that brings in fresh air and cools it with water. The air travels through tubes to cool it further. Finally, it blows into your home with an indoor fan motor.

Leaks will cause other parts of your HVAC system to become loose, freeze, or malfunction. This can cause a wide variety of problems and strange sounds. 

Loose Parts on Your Unit

If any of the parts in your HVAC system are loose, it could cause loud noises. Loose parts will vibrate against each other during operation. You’ll hear clanking or banging whenever your unit runs. In the Arizona heat, your system is likely running often.

Loose parts will get louder as they rattle out of place. Your HVAC expert will hear the sounds and know where to look for the loose part. Let them find the loose screw, pipe, or plate, and get it back in the right position.

Call An AC Expert 

Hearing some strange, disruptive noises from your AC unit that are crashing your peace and quiet? It sounds like it's time to bring in the pros. Those rattling and screeching sounds aren't just hard on the ears, they could be your AC's distress call signaling deeper issues.

An expert inspection and a thorough tune-up can calm those annoying noises and ensure your HVAC system is humming along nicely. 

For a swift and reliable AC diagnosis, you can count on the professionals at Parker & Sons. We're just a call away! Let us hit the mute button on those AC noises for good, helping you restore harmony in your home.

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