How to Fix / Troubleshooting

Safety first: Turn off power at the outdoor disconnect before touching the unit. Keep hands clear of fan blades.

Steps to reduce outdoor noise:

Inspect fan blade and motor: Check for wobbling blades, loose mounting, or rubbing against the shroud. Tighten or replace as needed.
Check motor bearings: Spin the fan by hand with power off; roughness or play indicates worn bearings. Replace the fan motor.
Listen to compressor: A loud grinding or metallic noise from the compressor often indicates internal failure; replacement by a technician is required.
Verify voltage: Low voltage can cause contactor chatter. Have an electrician correct any supply issues.

Do not attempt to open or repair the compressor shell; it is a sealed component.

Outdoor section of Amana central AC or heat pump is very noisy, with a loud humming or grinding sound.

Possible Causes