You flip the switch and hear a low hum, but nothing spins and nothing goes down. A garbage disposal humming but not working is almost always jammed: something is stuck between the spinning plate and the grinding ring, so the motor has power but can’t turn. The good news is that you can usually free it yourself in a few minutes, without taking anything apart.
Quick answer: turn the disposal off and switch off its power. Insert a hex key (Allen wrench) into the hole in the center underneath, and work it back and forth to free the jam. Remove the debris with tongs, press the red reset button, and test it with cold water running.
Safety first: never put your hand in the disposal
- Switch off the power before you do anything: unplug the disposal under the sink, or switch off its circuit breaker. Turning off the wall switch alone isn’t enough, because someone could flip it back on.
- Use tongs or pliers, never your fingers, to remove anything from inside.
- Don’t pour chemical drain cleaners into a disposal. They can damage it and splash back.
1. Turn it off straight away
If it’s humming, switch it off now. Leaving a jammed motor humming makes it overheat, and it may trip its own overload switch. Give it a few minutes to cool down.
2. Free the jam from underneath with a hex key
Most disposals have a small hexagonal hole in the very center of the bottom of the unit. Many come with a matching hex key (often 1/4 inch), sometimes stored in a little pocket on the side of the unit. A standard Allen key of the same size works too.
- With the power off, look under the sink and find the hole in the center of the disposal’s bottom.
- Insert the hex key and turn it back and forth. It will feel stiff at first.
- Keep working it until it turns freely in a full circle. That means the jam is cleared.
💡 Tip: Keep the disposal’s hex key taped to the side of the unit or to the inside of the cabinet door. Then it’s right there the next time a fruit pit or a stray spoon jams it.
3. Remove what caused the jam
Shine a flashlight down the drain opening and look for the culprit: fruit pits, bone pieces, bottle caps, a coin or a piece of cutlery are the usual suspects. Pull it out with tongs or long pliers.
4. Press the reset button
On the bottom or lower side of most disposals there’s a small, usually red, reset button. When the motor overheats or jams, this button pops out and cuts the power to protect the motor. Press it firmly until it clicks and stays in. If it won’t stay in, wait ten minutes for the motor to cool and try again.
5. Test it
Plug the disposal back in or switch the breaker back on. Run cold water into the sink, then switch the disposal on. It should spin freely and sound normal. Let it run with water for 15 to 20 seconds to flush away any leftover bits.
6. Not humming at all? Check the power
If there’s no sound at all when you flip the switch, it’s a power problem rather than a jam:
- Press the reset button, as in step 4.
- Check the circuit breaker, and reset it if it has tripped.
- Make sure the disposal is plugged in under the sink. Plugs get knocked loose by things stored in the cabinet.
- If the wall switch feels loose or doesn’t click properly, the switch itself may be faulty.
How to stop it jamming again
- Always run cold water while the disposal is on and for a few seconds after.
- Feed food in gradually, not all at once.
- Keep out fruit pits, bones, fibrous foods like celery and corn husks, and cooking grease.
- Check the drain opening for cutlery before you switch it on.
When to call a plumber or replace it
- It keeps humming even after you’ve freed the jam and pressed reset.
- The reset button trips again every time you use it.
- Water is leaking from the bottom of the disposal itself, which usually means internal seals have failed.
- It’s very old and grinds poorly even when it isn’t jammed.
Garbage disposal humming: quick FAQ
Why is my garbage disposal humming but not spinning?
Something is jammed between the turntable and the grinding ring. Freeing it with a hex key from underneath fixes this most of the time.
Can I use a broom handle instead of a hex key?
Some people push a wooden broom handle down the drain to turn the plate, but the hex key from underneath is safer and easier. Never use your hand.
Why does my disposal keep tripping the reset button?
Usually because it’s being overloaded or jammed often. If it trips even with light use, the motor may be wearing out.
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