Garbage Disposal Humming but Not Spinning? Here's the Fix
A humming disposal is almost always jammed. Here's how to free it safely with a hex wrench, reset it, and know when the motor is done and it's time for a new one.
If your garbage disposal hums when you flip the switch but nothing spins, the motor is getting power but the grinding plate is stuck. Nine times out of ten, something is wedged between the plate and the grinding ring: a bone, a fruit pit, a bottle cap or a spoon.
The fix takes about ten minutes and usually costs nothing.
Turn it off right away. Running a jammed disposal can overheat and burn out the motor.
What you need
- A 1/4-inch hex (Allen) wrench. Many disposals come with one, often called a jam-buster wrench.
- A flashlight
- Tongs or needle-nose pliers
- A broom handle or wooden spoon, if you don’t have the wrench
Step 1: Cut the power
Turn off the wall switch, then unplug the disposal under the sink or switch off its circuit breaker. Don’t rely on the wall switch alone. Never put your hand in the disposal, even with the power off.
Step 2: Look for the jam
Shine a flashlight down the drain. If you see something wedged, pull it out with tongs or pliers.
Step 3: Turn the motor by hand
Look at the center of the bottom of the disposal. Most have a small hex socket there.
- Fit the hex wrench into the socket.
- Work it back and forth until it turns a full circle freely. It may take some muscle at first.
- Remove anything that came loose with tongs.
No socket, or no wrench? With the power off, push a broom handle or wooden spoon handle down into the disposal against one of the lugs on the grinding plate, and lever it back and forth.
Step 4: Press the reset button
When a disposal jams, it often overheats and trips its built-in overload protector. Look for a small red button on the bottom or lower side of the unit. Let the motor cool for a few minutes, then press it until it clicks and stays in.
Step 5: Test it
Restore power, run cold water, and turn the disposal on. If it spins, let it run for 15 to 30 seconds with water to flush out any leftover bits.
Still humming?
- Repeat the hex wrench step. Some jams need a second try.
- Check for something small you missed, like a coin or a shard of glass.
- If the wrench won’t turn at all, the bearings may be seized or the motor may be failing.
- If it hums, then trips the reset button again, the motor is likely damaged.
At that point, replacing the disposal usually makes more sense than repairing the motor, especially on a basic unit. If the reset button won’t stay in, or it keeps overheating, call a plumber or replace it.
If it doesn’t hum at all
A silent disposal is a power problem, not a jam:
- Press the reset button.
- Check that it’s plugged in, and check the circuit breaker and any GFCI outlet under the sink.
- Test the outlet with another appliance.
- If there’s still nothing, the wall switch or the motor may be bad.
How to prevent jams
- Run cold water before, during and after grinding.
- Feed scraps in slowly, not all at once.
- Keep out: bones, fruit pits, corn husks, shells, grease, coffee grounds, pasta and rice. And keep utensils out of the sink when it’s running.
- Use a sink stopper when you’re not grinding, so nothing falls in.
FAQ
Where’s the reset button? Usually a small red button on the bottom of the disposal, or low on its side.
Can I use a drain cleaner on a jammed disposal? No. Chemical drain cleaners can damage the disposal and are dangerous to work around if you then have to clear it by hand.
How long do disposals last? It depends on the model and how hard it’s used. A longer warranty is a decent clue to build quality.
Shopping for a replacement? On a septic system, see the best garbage disposals for septic systems.