ScheduleDiagnostic guide
A/C making loud or unusual noise
Different noises point to different parts. A squeal is usually a bearing; a bang is often a loose panel or a failed compressor starting — don't ignore it.
01 / 04Likely causes
What is usually
behind it.
The shortlist of root causes we find on this call. The truck is stocked for most of these.
- 01Worn blower motor bearing (squealing from the air handler)
- 02Loose sheet metal panel or screw rattling
- 03Debris (leaves, sticks) caught in the outdoor fan
- 04Refrigerant liquid slugging in the compressor
- 05Failing contactor chattering on startup
- 06Duct expanding and contracting (clicking / ticking)
02 / 04Right now
Do this while you wait.
Steps that can save product, prevent damage, and shorten the repair once we are on site.
Do this
- Note when the noise happens — startup, during operation, or shutdown
- Check around the outdoor unit for visible debris
- If you hear a loud bang or clunk from the outdoor unit, shut the system off
Do not do this
- Do not reach into the outdoor unit while it is running
- Do not run the system if you hear metal-on-metal grinding — it will cause more damage
03 / 04On the truck
What our tech will check.
The diagnostic flow we run on this call. Most are resolved on the first visit.
- 01Inspect blower motor, capacitor, and fan blade for wear
- 02Clear debris and tighten loose panels
- 03Check refrigerant charge to rule out slugging
- 04Replace worn bearings or motors before they fail completely
Fast dispatch
Most calls see a tech in under two hours.
First-visit fix
Common parts on every truck.
Documented
Photos and notes attached to your ticket.
04 / 04Related service
This sits under
our hvac service.
Heating, cooling, and air handling for homes — diagnosed honestly and repaired without the upsell theater.
Related problems
Might also be one of these.
Other failures with similar symptoms or in the same trade.
Service request