Loud humming, buzzing, or grinding noise from outdoor unit
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power before removing the outdoor unit grille. Keep hands clear of fan blades.
Steps to check:
- 1. Inspect fan blade: Check for cracks, loose mounting nut, or contact with the grille. Tighten the fan hub nut if loose.
- 2. Remove debris: Clear leaves, twigs, or plastic from the fan area.
- 3. Check vibration pads: Ensure the outdoor unit is level and that rubber pads are in place under the base to reduce vibration.
When to call a technician: If the compressor itself is noisy (metallic knocking or loud humming) or if noise persists after fan checks, a technician should evaluate compressor health and mounting.
Repair Difficulty
Required Part
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