R-Pro › Field cases › Air conditioning
AC Fan Imbalance — Vibration / Noise on Rotation
Likely causes
Check blade damage, debris, shaft bend
Check: Visual blade inspection: cracks, missing chunks, debris (leaves/feathers/dust). Lost balance weight or asymmetric coating = wobble. Bent shaft = oscillation. Bearing fault = grinding + vibration. With system OFF, spin blade by hand to feel smoothness/balance.
What to do: Power OFF, check blade balance (manual spin: if one side feels heavy = imbalance). Cracks/missing = replace entire blade (no spot repair). Bent shaft = replace motor assembly. After work, verify vibration ≤4.5 mm/s RMS (ISO 10816 residential).
Fan imbalance = compounds bearing/motor damage. Address within 1 week. Damaged blade = replace whole blade (no spot repair). Aluminum blade bent = caused by external impact (mischief/careless service).
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
Open R-Pro →