Symptoms
- Fan runs noticeably slower than before on all or some speeds
- Fan hums but needs a manual push to start spinning
- One or more speed settings stop working while others still do
Likely causes
- CommonA degraded run capacitorCapacitors lose capacitance over years of use, gradually weakening fan performance before failing completely.
- CommonA capacitor with one of its internal sections failedMany fan capacitors have multiple sections corresponding to different speeds, and one section can fail while others still work.
- PossibleHeat damage to the capacitor from a hot attic space above the fanCapacitors in fans installed in hot spaces can degrade faster.
What to do
- Note exactly which speeds work and which don't, or if all speeds are just weaker than before.
- Turn off power to the fan at the wall switch and breaker.
- Remove the switch housing cover to locate the capacitor, usually a small rectangular component with several wires.
- Take a photo of the wiring before disconnecting anything.
- Note the capacitor's rated microfarad (uF) values for each speed, printed on its label.
- Replace it with an exact-match replacement capacitor, matching each wire to the same terminal.
- Call an electrician or fan technician if you're not comfortable identifying or matching the capacitor terminals.
Tools and parts
- Screwdriver
- Step ladder
Ceiling fan replacement capacitorSearch: “ceiling fan capacitor exact match microfarad”
When to call a pro
Call an electrician or fan technician if you're not confident matching capacitor ratings and wiring correctly.
Safety
Use caution
Turn off power to the fan before opening the housing, and take a photo of existing wiring before disconnecting the capacitor.