Symptoms
- Rattling, grinding, or buzzing sound when the fan runs
- Noise changes with fan speed
- Vibration felt on the hood housing
- Noise is new or has gotten worse recently
Likely causes
- CommonGrease buildup on the fan bladeAn unbalanced, grease-caked blade vibrates and creates noise as it spins.
- CommonLoose mounting screws or ductworkVibration over time can loosen screws holding the hood, motor, or ducting in place.
- PossibleWorn motor bearingsAging motors can develop a grinding or whining noise as internal bearings wear down.
- PossibleDebris caught in the fan or ductA stray object or heavy debris buildup can rattle against the spinning blade.
What to do
- Turn off power at the breaker before removing any covers or filters.
- Remove and clean the grease filter thoroughly, either by hand or in a dishwasher if it's dishwasher-safe.
- Clean the fan blade itself of grease buildup using a degreaser and cloth.
- Check and tighten any visible mounting screws on the hood body and duct connections.
- Turn power back on and listen for the noise at different speeds to see if cleaning resolved it.
- If a grinding or whining sound remains after cleaning, the motor bearings may be worn and the motor may need replacement.
Tools and parts
- Screwdriver
- Degreaser
- Cloth
Range hood fan motorSearch: “range hood exhaust fan motor replacement”
When to call a pro
Call an appliance technician if cleaning doesn't quiet the fan, since a worn motor likely needs replacement.
Safety
Use caution
Turn off power at the breaker before cleaning near the fan motor or removing covers.