weird noises

Why is My AC Making Weird Noises? When You Should Be Concerned

Is your air conditioner making noise?

Air conditioners should be felt, but not heard for the most part. Especially the newer units, designed for a cool quiet.

If you hear weird noises coming from your ac unit, it might need repair. Do you know what to listen for?

A Guide to Weird Noises From Your AC

While some noises can happen every now and then, others call for immediate ac repair! Keep reading to learn when to worry about your unit and what each sound might indicate.


Think of a nose similar to when people cheers their glasses. This may not signal any problems.

When the electrical parts of your ac first startup, or shut down, they may make this noise. But, you should not hear this constantly.

It could mean that your thermostat needs replacement. Or, it could signal a problem with one of the other controls or electrical parts.

Get this fixed as soon as possible. Though it’s probably a simple repair, electrical problems do pose a fire hazard.


This noise sounds more like a drawer full of silverware getting moved around. It probably indicates an obstruction of some sort.

If you hear it from the fan outside or the blower on the indoor ac unit, then you might hear the blades hitting something. Maybe a people or stick fell into the unit outside, or possibly the blades actually moved out of balance.

This calls for immediate attention. Though not a major issue now, it can turn into one quickly.


Do you hear a knocking noise? This typically indicates a broken part inside the ac compressor.

It could be the crankshaft, piston, or a connecting rod. But, it could also mean that you need a new compressor altogether. Your unit needs all of these parts to actually function.


Does it sound similar to shaking a rattle? This could mean a number of things.

Best case scenario, a rattling noise means that you need debris cleaned out of a clogged system. It could also indicate loose parts somewhere. But, it may also signal a broken electrical contractor.

Clean any debris out of the system and tighten up the bolts. If that does not work, then you need a big repair.

Humming or Buzzing

A light hum might indicate that a part moved a little out of place, or something simple with the cooling unit. A persistent buzzing though could indicate anything from parts out of place to more serious electrical issues.


If you hear a sharp train whistle, shut off your unit. Do not run it at all until somebody comes to repair it.

This noise most likely indicates a freon leak. It is toxic and potentially lethal to you, your family, and your pets. Take this issue seriously.

Stay Cool

Don’t get caught in the heat! If your air conditioning unit starts to make weird noises, listen to what it’s telling you. We want to help keep your family comfortably cool and safe.

Please contact us for all of your heating and cooling needs!

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