Like the peaceful sound of rolling ocean waves or a babbling brook, most air conditioners make a gentle whooshing sound when operating. Alright, so maybe your AC isn’t quite as tranquil, but it should be fairly quiet.
Weird sounds are some of the best indicators that something is wrong with your AC unit. Unusual sounds coming from your air conditioning unit may indicate problems, but in order to diagnose the specific issue, you’ll need to know exactly which of these sounds your unit has been making.
If your air conditioner is making any of these noises, don’t ignore it – it’s asking for help!
11 Air Conditioning Noises You Never Want to Hear & What They Mean
Here’s why your AC might be making those weird sounds and what you can do about it:
1. Grinding Noise
Sometimes, noises coming from your AC unit mean you should shut them off right away. A grinding noise is one of them. If you hear a grinding noise coming from your unit, be sure to shut your AC off at the thermostat.
Grinding is typically caused by a faulty condenser motor. The bearings inside the motor may be worn out and need to be repaired or replaced. Similarly, the fan blade may be broken and rubbing on other components. Either way, broken, faulty, and old parts are bad news for your AC, which is why you should turn your unit off and call a professional.
2. Humming Noise
If your air conditioner is making a humming noise, the culprit is likely dirt or dust. When air conditioning units get dirty, debris can impede the fan’s circulation inside the unit. This can result in a loud humming noise. No reason to fret though. With a little practice (and patience), you can clean your air conditioning unit yourself.
Start by removing any excess weeds that have grown around the unit. Once the weeds are removed, take the top of the unit off and use a brush or cloth to gently wipe down any dirty or dusty components.
3. Buzzing Noise
Buzzing is almost always a sign of an electrical issue. If buzzing only occurs when triggering certain settings through your control panel, it’s likely just a faulty part. But if the buzzing is constant, it’s more likely to indicate a problem with the wiring, like a loose or exposed wire, causing electricity to spark within the unit.
Slight humming is common and usually doesn’t mean anything serious. On the other hand, if your air conditioner is making loud buzzing or popping noises or you can see visible sparking, it could be a sign of loose parts, motor problems, or something else. We recommend having a professional technician inspect the situation sooner rather than later.
4. Screeching Noise
If you hear screeching coming from your AC unit, it’s best to turn it off as soon as possible. Screeching can be indicative of pressure building up and trying to escape within your compressor. While there are safety precautions installed to turn off the unit when this is detected, it’s still possible for this issue to occur.
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5. Rattling Noise
Rattling noises typically indicate a loose screw, nut, fastener, bolt, or another small part within your AC unit. Listen carefully to find where the sound is coming from. Check to see if anything is loose. You may be able to quiet your AC with the simple twist of a screwdriver.
It can also indicate that a piece of your unit has broken off and is vibrating on the bottom of your unit as your air conditioner functions or be caused by parts of your unit being too close to the walls of your air conditioner.
If you hear a rattling noise coming from your outdoor condenser unit, it may also mean that debris (think leaves and twigs) has gotten inside the unit. You should be able to remove any foreign objects by removing the fan grill. Just be sure to turn the unit off first.
If you still haven’t landed at a diagnosis, the issue may lay in your compressor, which is usually a sign your AC is on its last leg.
6. Clicking Noise
A clicking sound can be dangerous because it’s often indicative of an issue with your air conditioner’s electrical connection. It’s common for your AC to click once when it first turns on, but continued clicking is not normal.
Clicking is a vague sound to hear in an AC unit. Like rattling, it could imply that a part is loose and is hitting another part within your unit, but it could also indicate that your fan is brushing up against something as it’s spinning.
Clicking sounds may mean there is an electrical issue within your control panel. Faulty electrical signals create clicking noises with tiny sparks of electricity and by continuously causing switches to turn on and off. If you hear clicking along with loud popping or see sparking, turn your AC unit off and call for professional help.
7. Squealing or Squeaky Noise
If your air conditioner is making a squealing or squeaky noise, more than likely the fan belt is loose. You may need to have it replaced or simply readjusted.
A loose fan belt repair is not for an air conditioning novice so make sure to call a professional technician if yours needs to be replaced.
8. Bubbling or Gurgling Noise
Double, double, toil and…bubble? If your air conditioner is making a bubbling or gurgling noise, no need to be frightened. A bubbling or gurgling noise isn’t common, but the problem likely isn’t a big issue.
Bubbling or gurgling coming from your AC unit occurs when the condensate pump malfunctions. As condensate builds up with your unit, it drips to the bottom of the air handler where it empties into a drain pan via gravity or a condensate pump. When something goes awry with the pump and water backs up, it can lead to these noises.
Having a new condensate pump installed is simple, but don’t wait too long to have it checked out by a professional since water build damage is a very real possibility.
9. Hissing Noise
Hissing sounds indicate that there is probably a leak lurking somewhere, if you hear a hissing sound coming from your AC, it’s likely either a ductwork issue or a refrigerant leak.
There may be a leak in your ducts allowing air or refrigerant to escape. If air is leaking, and your system is not running efficiently, while refrigerant is also leaking, your family may be exposed to a dangerous chemical, so call an AC professional right away.
Unfortunately, this is usually not an easy repair, even for most professionals. Since there are so many areas within the intricate system that is an AC, it can be difficult to locate the leak yourself. Make your life easier and call a professional.
10. Banging Noise
If your air conditioner is making a banging noise, don’t be spooked. A banging noise could mean a few things, but it’s usually a sign that something inside the AC has come loose. A small part like a screw, spring, or bolt could have gotten loose and is being thrown around or something just may need to be tightened. Luckily, these scenarios are all easy fixes.
Banging can also be the result of broken parts within your compressor or an incorrect mounting of your compressor. If you see any shaking or broken pieces within your unit while it’s on, that’s likely the culprit. If not, the problem may require professional assistance.
11. Loud Whistling
When your air conditioner kicks on, do you hear a loud whistling coming from the air vents? This noise occurs when there is low airflow, meaning too little air is moving through the return vents. Low airflow is typically caused by blocked air vents, a dirty air filter, or a closed damper.
Each of these potential culprits is easy to address. Blocked air vents are remedied by simply cleaning the vent grills and removing any debris in their way. Dirty air filters can impede airflow, so we recommend changing them monthly, for good measure. As for the dampers, these are the metal levers in your ductwork. Dampers can be accidentally shut, causing poor airflow and subsequent whistling. To remedy this, simply check that the dampers are aligned with the grills of the air vents.
If the whistling persists after you’ve checked these off your list, we recommend calling a professional for a diagnosis.
Contact Climate Design for AC Repair in the Tampa Bay Area
At Climate Design, our experienced professionals speak AC fluently. If your air conditioner is making an unusual or alarming sound, call us for an accurate diagnosis and efficient repair. We’ll have your AC quieted down and running smoothly in no time. Give us a call or schedule service online today.
Call (888) 572-7245 to Schedule Your Appointment