Symptoms
- Buzzing or humming from the back or bottom of the fridge
- Clicking sounds every so often
- Rattling or vibrating noise
- Loud whirring or grinding from inside the freezer
Likely causes
- CommonCondenser fan hitting debris or dust buildupA fan blade rubbing against accumulated dust or a bent guard can cause rattling or grinding.
- CommonEvaporator fan icing over or wearing outIce buildup on the fan blades in the freezer, or worn bearings, causes a whirring or grinding sound.
- CommonCompressor cycling normallyA brief humming or clicking when the compressor starts and stops is normal operation, not a fault.
- PossibleFridge not level, causing vibration against nearby surfacesAn unbalanced fridge can vibrate against a wall or cabinet, amplifying normal operating sounds.
- PossibleFailing compressorA loud, continuous grinding or knocking from the compressor itself can indicate it's wearing out.
What to do
- Pull the fridge out and listen closely to identify whether the noise comes from the back (compressor/condenser fan) or inside the freezer (evaporator fan).
- Clean the condenser coils and fan area of dust buildup, which often quiets a rattling or humming noise.
- Check that the fridge is level using a small level tool, adjusting the front feet if it rocks or vibrates against a wall.
- If the noise is inside the freezer, check for ice buildup around the evaporator fan panel, which may indicate a defrost issue.
- Make sure nothing (like a bottle or dish) is touching the back panel or vibrating against the fridge itself.
- Listen for whether a loud noise happens only during defrost cycles, which can point to the defrost heater or evaporator fan.
- If a grinding or knocking noise comes specifically from the compressor and doesn't stop, professional diagnosis is needed.
Tools and parts
- Small level
Refrigerator evaporator fan motorSearch: “refrigerator evaporator fan motor”
Refrigerator condenser fan motorSearch: “refrigerator condenser fan motor”
When to call a pro
If the noise is a loud knock or grind from the compressor itself, have an appliance technician evaluate it, since compressor replacement is a bigger job.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.