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commercial air conditioners

5 Strange Air Conditioner Noises Explained

Is your air conditioning system making noises that you haven’t noticed before? While no air conditioner runs silently, it’s a good idea to pay attention to the noises it makes because certain sounds can indicate a problem.

Here are some of the more common sounds reported to HVAC technicians, along with what usually causes these sounds.

1. Banging, Knocking, or Clanking

These sounds are heard from an air conditioning system’s outdoor unit (the condenser), and they generally indicate that there is something disrupting the unit’s fan. Sometimes something might have loosened the fan or its blades, causing them to hit other parts of the unit. It’s also possible that the fan is hitting an object that fell inside of the unit.

If you hear banging, knocking, or clanking sounds coming from the condenser, turn the system off and call a technician so that you don’t risk damaging the fan or another part of the unit.

2. Clicking

Loud clicking is a sign of several possible issues, making this problem difficult to troubleshoot without an expert. What you can do is try to determine when the clicking occurs.

If the clicking occurs when the unit is running, there may be something obstructing the fan in the outdoor unit. If your AC is clicking and won’t turn on, you could be dealing with an electrical issue stemming from a problem with the thermostat, capacitor, or compressor.

3. Squealing

You’ll hear this sound when the unit is running, and it usually indicates that there’s a problem with the unit’s fan belt. Over time, a belt can become misaligned or simply worn down. If you hear this sound, refrain from running your unit (or else risk breaking the belt), and contact a technician.

4. Screeching

This particularly alarming noise coming from your AC’s outdoor unit might also sound similar to a hiss, a scream, or metal scraping against metal. It will occur after the unit is turned on and will last for approximately 15 seconds.

If the sound is more like a hiss, it’s a strong indicator that there’s high pressure in your AC’s compressor. If the noise is closer to a metal-on-metal sound, the fan motor will probably need to be replaced due to worn-out bearings.

5. Bubbling

If your air conditioner starts to make a gurgling or bubbling sound after it turns on, this usually means that there is an issue with either the drain line or the refrigerant. While it may be possible for you to conduct a repair on the drain line yourself, refrigerant issues require special training and should always be handled by a professional.

If your business’s air conditioner is making odd noises and exhibiting strange behavior, there could be a number of explanations. At Del-Air Mechanical, our Knoxville team of commercial HVAC experts can pinpoint the issue and provide you with solutions that always keep your best interests in mind.