The essentials in 30 seconds
A disposal that hums but does not spin is jammed: switch it off and turn the hex socket on the bottom with a 1/4-inch Allen wrench until the plate spins freely. A disposal that is completely silent has usually tripped its overload: press the small red reset button on the bottom, and check the breaker if that fails. If it runs but the sink will not drain, the clog is in the drain pipe, not the disposal. Never put your hand inside the unit.
- Run a steady flow of cold water before, during and a few seconds after grinding.
- Keep fats, oils and grease out of the disposal and the drain, always.
- A leak from the body of the unit itself usually means it needs replacing.
Garbage disposal not working: find the cause by symptom
| What happens | Likely cause | What to do |
|---|---|---|
| Hums but the plate does not turn | Jammed plate: a bone, pit, bottle cap or packed scraps | Power off, free it with the hex key, remove the object, press reset |
| Completely silent | Overload protector tripped, breaker off or plug loose | Press the red reset button; check the breaker, plug and switch |
| Runs a few seconds, then stops | Overheated from a jam or too much food at once | Clear the jam, let it cool, then feed scraps gradually |
| Runs, but water stands in the sink and you see a whirlpool | Clog in the drain line or trap beyond the disposal | Plunge the drain; see clearing the drain below |
| Runs, water stands, no whirlpool | Plate jammed or packed solid | Treat it as a jam |
| Loud metallic rattling | Spoon, coin, ring or bottle cap inside | Power off, find it with a flashlight, lift it out with tongs |
| Bad smell | Food stuck under the rubber splash guard and on the chamber walls | Scrub the splash guard and run cold water with ice |
| New disposal, dishwasher will not drain | Knockout plug still in the dishwasher inlet | Remove the plug from the inlet |
| Water under the sink | Leak at the mounting, discharge, dishwasher inlet or body | See leaks by location below |
How to reset a garbage disposal
Every disposal has an overload protector that cuts the motor when it overheats, usually because of a jam or a long run with too much food. On most units it is a small, square red button on the bottom, facing the floor.
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01
Switch off
Turn the wall switch off, or unplug the unit if it has a push-button air switch on the counter.
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02
Find the button
Look under the sink at the base of the disposal. A tripped button sits about 1/4 inch (5 mm) lower than normal.
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03
Press it gently
It should click and stay in. If it pops back out, wait 10 minutes for the motor to cool and try again.
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04
Test with water running
Turn on the cold water, then the disposal.
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05
Still silent?
Check the circuit breaker or fuse for the kitchen, then the plug and the switch. Some models reset themselves automatically after cooling for up to 20 minutes, so give them that time before you call anyone.
If the button trips again straight away, the plate is still jammed or the motor is failing. Free the plate before you press it again.
How to unjam a garbage disposal with a hex key
Most disposals have a hex socket in the center of the bottom. It turns the motor shaft directly, so you can free the plate by hand from below without reaching into the chamber. The unit often comes with a small bent wrench for this; a standard 1/4-inch Allen wrench fits too.
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01
Power off and water off
Wall switch off and the unit unplugged or on a switched-off breaker. If the sink is full, let it drain or bail it out.
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02
Fit the hex key
Push it into the socket at the bottom center of the disposal.
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03
Work it back and forth
Rock it like a crank. Some force is fine: the supplied wrench is designed to bend before the disposal is damaged.
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04
Keep going until it spins freely
The plate is free when the wrench turns full circles in both directions.
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05
Remove the culprit
Shine a flashlight into the chamber, especially around the outer edge of the plate where the small teeth are, and lift out anything hard with tongs or pliers.
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06
Press reset
Check the red button and press it if it has tripped.
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07
Test
Cold water on, then the disposal. If it jams again, repeat the process; stubborn jams sometimes need several rounds.
Some models have no hex socket. Their manuals usually tell you to rotate the plate from above with the handle of a wooden spoon, with the power off, then lift the object out with tongs.
When the disposal runs but the sink will not drain
If the motor runs and you can see a whirlpool forming in the standing water, the disposal is doing its job and the blockage is further along the pipe.
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01
Power off
Switch off and unplug the disposal.
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02
Clean the splash guard
Scrub the underside of the rubber baffle and the top lip of the chamber with a scouring pad; packed food here slows draining and smells.
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03
Flush
Fill the sink halfway with warm water, add about 1/4 cup of baking soda, then pull the stopper and run the disposal at the same time.
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04
Plunge
If water still stands, plug the other bowl of a double sink, leave about 4 inches (10 cm) of water in the sink, place a cup plunger over the disposal opening and push down slowly, then pull up sharply. Repeat several times.
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05
Run it clear
Once it drains, run water and the disposal for one to two minutes.
If plunging fails, the trap or the branch drain is blocked. Our guide on how to unblock a sink covers opening the trap. If several fixtures back up at once, the problem is the main line: see sewer cleanout.
Skip chemical drain openers. The EPA advises against them on septic systems, the disposal maker advises keeping harsh cleaning products out of the unit, and a sink full of caustic water makes plunging or opening the trap far riskier.
Leaking garbage disposal: what the drip location tells you
Before you fix anything, find the exact spot. Empty the cabinet, tape newspaper across its floor and dry every surface. Then fill the sink and let it stand, pull the plug and let it drain, and finally run water and the disposal, checking for drips at each stage.
| Where it drips | Usual cause | What to do |
|---|---|---|
| Top, where the unit meets the sink | Loose mounting ring or screws; on a new installation, excess plumber's putty under the sink flange | Turn the locking ring fully to the right and tighten the three mounting screws; if the putty is the problem, remove the unit, scrape the excess and remount |
| Side, at the dishwasher hose | Loose hose clamp or a worn hose adapter | Tighten the clamp and replace a split adapter |
| Side, at the drain pipe (discharge) | Loose discharge bolts or nut, a cracked or dirty gasket, a cracked elbow | Snug the fasteners, clean or replace the gasket, replace a cracked elbow and tighten the joint at the trap |
| Bottom, at the reset button or the base | Water running down from a leak higher up, or failed internal seals | Rule out the top and side first; a leak from the body itself usually means replacement |
| Paper stays dry for days | The water comes from elsewhere | Check the faucet, sprayer, water filter, dishwasher drain hose and the sink-to-countertop seam |
What never to put in a garbage disposal
What a disposal can grind depends on its motor and grinding parts, so check your manual. These rules hold for almost every unit and every drain:
- Fats, oils and grease: they set in the pipes further down and cause blockages in your drain and in the street sewer.
- Stringy, fibrous peels such as celery, banana peels, corn husks and rhubarb on basic models: they wrap around the plate.
- Large bones, meat trimmings and fruit pits, unless your manual says the model handles them.
- Non-food items: glass, metal, plastic, cigarette butts, wipes, paper towels.
- Harsh chemicals and drain openers.
- Big batches all at once: feed scraps gradually with the water running.
How to use it so it lasts:
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01
Cold water first
Start a steady flow of cold water, then switch the disposal on.
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02
Feed gradually
Add scraps a handful at a time; the sound changes when the chamber is empty.
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03
Flush
Switch off, then let the water run a few more seconds to carry the scraps down the drain.
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04
Avoid hot water while grinding
You can run hot water between uses to rinse the pipe.
On a septic system, every scrap you grind adds solids to the tank, so the EPA advises limiting disposal use and expecting to pump more often; see our guide to septic tank pumping. In the UK the same appliance is usually called a food waste disposer, and the troubleshooting steps are the same.
When to replace a garbage disposal instead of fixing it
- Water leaks from the body of the unit or the base, after you have ruled out the mounting, the discharge and the dishwasher inlet.
- The motor hums even though the plate spins freely by hand with the hex key.
- The overload trips repeatedly after you have cleared every jam and let the motor cool.
- The unit is rusted through or cracked, or grinds poorly despite a clean chamber.
Before you buy, check the model and serial number on the label underneath: the manufacturer can tell you whether the unit is still under warranty. Some brands design new units to twist onto the existing mounting, which makes a like-for-like swap simpler. If the new unit must be hard-wired, or you are not sure the circuit is suitable, ask an electrician to make the connection.
Garbage disposal not working: frequently asked questions
Why is my garbage disposal humming but not working?
The plate is jammed. Switch off and unplug it, turn the hex socket on the bottom with a 1/4-inch Allen wrench until it spins freely, remove the object with tongs and press the reset button.
Where is the reset button on a garbage disposal?
On most units it is a small red button on the bottom, under the sink. A tripped button sits slightly lower than normal.
Why won't my garbage disposal turn on?
The overload protector has tripped, the breaker is off or the plug is loose. Press reset, wait 10 minutes if it pops out, then check the breaker.
How do you unjam a garbage disposal?
With the power off, rock a hex key in the socket at the bottom until the plate turns full circles both ways, then lift out the object with tongs. Never use your hand.
Why is my garbage disposal leaking from the bottom?
Water often runs down from a loose mounting or drain connection above. If those are dry and the body itself leaks, the internal seals have failed and the unit needs replacing.
Can I pour drain cleaner into a garbage disposal?
It is best avoided: manufacturers advise against harsh chemicals, and caustic water makes plunging risky. Use a plunger, then open the trap.
Can you put ice in a garbage disposal?
Yes. Ice cubes with lemon or lime wedges, run with cold water, help clean the chamber after you scrub the splash guard.
Can I use a garbage disposal with a septic tank?
You can, but it adds solids to the tank. Use it sparingly and plan to have the tank pumped more often.
Sources
Manufacturer and public agency guidance, checked on 27 October 2026.
- InSinkErator · Fixing a jammed garbage disposal ↗Hex socket and 1/4-inch Allen wrench, working the plate free, red overload button, wooden spoon method on some models, automatic reset after up to 20 minutes, checking the breaker.
- InSinkErator · Resetting a garbage disposal ↗Button position, 5 mm drop when tripped, 10-minute wait.
- InSinkErator · Fixing a clogged garbage disposal ↗Whirlpool test, cleaning the baffle, baking soda flush, plunging with 4 inches of water.
- InSinkErator · Garbage disposal leaking (mounting, discharge and dishwasher inlet) ↗Checks at each connection, knockout plug, putty, newspaper test and other leak sources.
- InSinkErator · How to use a garbage disposal and FAQ ↗Cold water, gradual feeding, flushing, no grease, fibrous items on standard models, harsh cleaners.
- US EPA · How to care for your septic system ↗Avoiding chemical drain openers and limiting disposal use on septic systems.
- FEMA · Urban flooding: guidance for homeowners and renters ↗Keeping grease, meat and bones out of the disposal to avoid sewer clogs.
Still humming after the hex key?
Note the model number on the label underneath before you call a plumber or the manufacturer.