Quick Answer:
You flip the switch, hear a hum, and nothing turns. First, turn it off immediately and confirm the unit is not spinning. Then check for obvious debris at the opening. The hum usually means the motor is getting power but the blades are jammed or overloaded; acting quickly and safely can prevent the motor from burning out.
Why This Happens
- The motor gets power but the impeller (the part that spins) is blocked by a foreign object or hardened material.
- Large or hard food pieces, silverware, or fruit pits can lodge between the impeller and the housing.
- Grease or fibrous foods can bind up the blades so they can’t turn.
- An electrical fault or a seized bearing is less common but possible if the unit is old or has been overheating.
Step-by-Step What to Do
1. Cut the power and confirm it’s not spinning
- Turn the switch off immediately and confirm the unit is not spinning. Don’t rely on the switch alone—if you can, flip the circuit breaker for the disposal to be safe.
- Leave the breaker off until you’ve completed the checks below.
2. Look for obvious debris at the opening
- With the power off, use a flashlight to look down the opening. Then check for obvious debris at the opening.
- Use long-handled tongs or pliers to remove any visible pieces—never put your hand inside the unit.
- If the jam looks like it came from a hard piece of food, see Disposal jammed after hard food for more on removing that kind of object.
3. Try freeing the impeller from below (if accessible)
- Most disposals have a small hex socket centered on the bottom. With the power off at the breaker, insert the manufacturer-supplied hex wrench or a 1/4″ hex key and work it back and forth to free the impeller.
- If the impeller moves freely, remove the wrench and restore power briefly to test.
4. Use ice or a wooden tool carefully (optional)
- Sometimes using a handful of ice cubes and running cold water while briefly powering the unit can loosen stuck bits, but only after you’ve removed any visible foreign objects. If you want details on using ice safely, read Disposal jam after ice cubes.
- Alternatively, use a wooden spoon handle to gently rotate the impeller from the top opening while the power is still off.
5. Press the reset button and test
- Find the reset button on the bottom or side of the unit. If it has tripped, press it after you’ve cleared jams and returned the unit to the neutral position.
- Restore power at the breaker, run cold water, and test with the switch for a short time to confirm the unit spins and sounds normal.
6. If it still hums, stop and get help
- If the motor still only hums after you’ve tried the safe clearing steps, switch the breaker off again and move to the “When to Call a Professional” section below.
What Not to Do
- Do not keep holding the switch while it hums—this can overheat the motor fast.
- Do not put your hand inside the disposal, even with the power off unless you are certain the unit is disconnected and you are following the manufacturer’s instructions.
- Do not pour chemical drain cleaners into the disposal; they can damage the unit and present safety hazards.
- Do not try to disassemble the motor housing yourself unless you have experience and the correct replacement parts.
When to Call a Professional
- The unit continues to hum with no movement after you’ve removed visible obstructions and tried the manual hex-wrench method.
- You smell burning or see smoke — stop immediately and call for help.
- The disposal leaks, the reset button won’t stay engaged, or the circuit breaker trips repeatedly.
- The unit is old, has a seized bearing, or you’re not comfortable performing the safe checks yourself.
Safety Notes
- Always turn off the disposal at the circuit breaker before working on it. Confirm power is off with a tester if you have one.
- Use tools (tongs, pliers, hex wrench) instead of your hands. Wear eye protection and work gloves.
- Keep water off electrical components. Run cold water only when testing with power on.
- Follow the manufacturer’s instructions for your specific model when available.
Common Homeowner Questions
- Why does it hum but not turn? — The motor is receiving power but the impeller is blocked or jammed so it can’t rotate.
- Can I fix it myself? — Often yes for simple jams if you follow the power-off safety steps and use tools instead of your hand.
- Will running water help? — Cold running water helps when testing or flushing out debris, but don’t run the unit while it’s humming under load—first clear the jam with power off.