AC Making Noise

Different sounds usually point to different problems — here's a plain-English breakdown.

Grinding

Often points to a motor bearing wearing out — usually worth addressing before it fails completely and causes a bigger repair.

Squealing

Commonly a belt or motor bearing issue, similar to a squealing sound from a car engine.

Clicking (repeated, not just at start/stop)

Can indicate an electrical relay issue or a failing capacitor — worth having checked rather than ignored.

Banging or clanking

Often a loose or broken part inside the unit — continuing to run the system can cause further internal damage.

Hissing

Can indicate a refrigerant leak, which needs professional handling — refrigerant work requires certification.

Buzzing

Frequently an electrical issue — loose wiring or a failing component drawing irregular current.

Frequently asked questions

Is it safe to keep running my AC if it's making noise?

Depends on the sound. A single click at startup/shutdown is normal. Continuous grinding, banging, or hissing is worth turning the system off and having it inspected before running it further.

Do all AC units make some noise?

Yes — normal operation includes some fan and compressor sound. What matters is a change from your system's normal sound, or new sounds that weren't there before.

See our full AC Repair service or browse other common symptoms.