Garbage Disposal Not Working: Humming, Won't Turn On, Draining Slowly, or Leaking

A garbage disposal that goes silent, hums without spinning, leaves water in the sink, or drips into the cabinet usually points to a short list of causes: a tripped reset button, something wedged inside, a dead outlet, a clog past the disposal, or a loose connection, and the first checks cost nothing.

Below, the symptoms run from easiest to hardest, following what InSinkErator, Moen, and Waste King tell their customers, and where a plumber or electrician takes over. You need a flashlight, tongs or pliers, and, for many units, the hex wrench that came in the box.

First, Check What Is Normal

Know how yours gets power. A cord to an outlet under the sink means a plug-in unit; a cable from a plate on the bottom into the wall or a metal box means it is hardwired. InSinkErator's troubleshooting starts here, because the checks differ.

Know how it switches on. Many use a wall switch. An air switch is a push button on the sink with a tube to a box underneath; Moen says to check that the tube is connected and undamaged. A batch-feed disposal has no switch: per Waste King, it runs only when its stopper is set in the right way and pressed down.

Most Likely Causes

1. Silent: the reset button has tripped. InSinkErator says the red overload button on the bottom shuts the motor off if the unit jams, runs a very long time, or has another problem; tripped, it sits about a quarter inch low. With the switch off, let the motor cool (3 to 5 minutes, per the manual), then press it gently; if it won't stay up, wait ten minutes and try again. Moen's button is opposite the power cord and may need a screwdriver tip. InSinkErator's EZ Connect, Builder Series, Amana, and ES units have an automatic overload instead: switch off and let the motor cool for up to 20 minutes, and on an air switch, unplug the unit for that time. If a jam tripped it, clear the jam first.
2. Silent: no power at the outlet, switch, or breaker. InSinkErator's test: unplug the disposal, plug a lamp into its outlet, turn the lamp on, and flip the wall switch a few times. If the lamp follows the switch, the power is fine and the disposal needs service. If not, check the breaker or fuse (see resetting a breaker safely) and any GFCI: the CPSC notes that a GFCI outlet also protects the outlets downstream of it, so one that tripped elsewhere can cut power under the sink (see GFCI won't reset). If the outlet stays dead, InSinkErator and Moen both send you to an electrician. On a hardwired unit, check the breaker and the reset button; past that, InSinkErator says the problem may be in the disposal or the electrical system, and the wiring is an electrician's job.
3. Humming but not spinning: it's jammed. Something such as a bone or a spoon is wedged in the grinding parts, and Moen says the motor hums because it can't turn; repeated tries can trip the overload. Switch it off and disconnect the power. On most InSinkErators, bail out any standing water, fit the wrench into the hex hole at the dead center of the bottom, and work it back and forth like a crank until it turns full circles in both directions; on its Builder Series, Amana, and ES units, InSinkErator instead has you turn the turntable from above with a wooden spoon, power off. Some force is fine, InSinkErator says, since the wrench is designed to bend before the disposal is damaged. Remove the wrench (never hold it while the unit runs, the manual warns), lift out anything you see with tongs, press the reset button, restore power, and run cold water, then the disposal. It may take a few rounds. Every InSinkErator ships with the wrench, and InSinkErator says a standard 1/4-inch Allen wrench also works. Moen and Waste King have you turn the plate from above instead, power off, with Moen's un-jamming wrench or, for Waste King, a wooden spoon handle against the impellers.

4. It trips the reset button again and again. Clear the jam completely, feed scraps in gradually with cold water running instead of pre-loading the chamber, as InSinkErator directs, and let the motor cool. If it still trips with the plate turning freely and the chamber empty, stop resetting it and see When to Call a Pro. If the house breaker is what keeps tripping, NFPA lists frequent tripping as a reason to call a qualified electrician.
5. It runs, but the sink drains slowly. Turn the disposal on with water in the sink. If you see a whirlpool, InSinkErator says, the drain line may be clogged. Its fix is a plunger: switch the disposal off and disconnect its power, as InSinkErator's clog steps say, then on a double sink, stopper the other drain, run about 4 inches of water, and plunge over the disposal opening. If that fails, see our slow or clogged drain guide.
6. It runs but won't grind, or it rattles. InSinkErator's two swiveling impellers must move freely; with the power off, push each with a spoon handle. If they're stuck, it suggests grinding a few fruit pits or beef round-steak bones with the water running, and service after three tries. For clicking or metallic rattling, look for a foreign object with a flashlight and remove it with tongs. A loud vibration can mean loose plumbing or an unlocked mounting ring.
7. It leaks. Moen's test: fill the sink, wrap paper towels around the sink flange, the drain elbow, and the dishwasher hose connection, then drain the sink and see which towel gets wet. At the top: a worn gasket or sealant or loose mounting screws, per Moen. At the dishwasher inlet: tighten the clamp or replace the connector. At the drain elbow: tighten the bolts or replace a cracked gasket; Moen notes a bad elbow gasket can leak out the bottom plate and pass for a body leak. Through the body, the bottom, or the motor joint: once you've ruled out a drip from above, InSinkErator says to contact them for service.
8. It smells. InSinkErator says an odor usually means food buildup under the rubber baffle and in the grind chamber. With the power disconnected, scrub the underside of the baffle with a scouring pad, then stopper the sink, fill it halfway with warm water, mix in 1/4 cup of baking soda, and turn the disposal on as you pull the stopper. Moen adds that a slow drain can cause odors, too.

What You Can Fix Yourself

• Press the reset button, switch off, after the motor cools.
• Free a jam with the hex wrench, or your brand's tool from above, and lift objects out with tongs.
• Test the outlet with a lamp, and reset a tripped breaker or GFCI once.
• Plunge a clogged drain line.
• Tighten the mounting screws, hose clamp, and drain elbow bolts, and replace a cracked gasket.
• Clean the baffle and flush the chamber with baking soda.

When to Call a Pro

An electrician for an outlet that stays dead, a breaker that keeps tripping, a burning smell, or a hardwired unit's wiring. InSinkErator's manual adds doubts about grounding and a plug that doesn't fit the outlet, which you should never modify or force. A plumber for a clog you can't plunge or leaks in the pipes past the disposal.

Replace it, or get warranty service, when it won't run with power at the outlet and the reset pressed (Moen says it may need replacing; Waste King says a unit that turns freely, with the reset and the wiring, switch, and breaker all fine, may have internal mechanical problems that require replacement), keeps tripping with nothing jammed, or leaks through the body. Check the warranty first: InSinkErator's in-home limited warranty runs 2 to 6 years on its Badger models and is void if you attempt to repair the unit. Our DIY vs. hire-a-pro guide rates installing a disposal as careful DIY, and InSinkErator says its Quick Lock mount lets one InSinkErator twist off and another twist on. That means swapping a plug-in unit for a corded one, with the power disconnected first, as the manual requires; wiring a hardwired unit, or adding an outlet under the sink, is an electrician's job.

Prevent It

Follow InSinkErator's routine: cold water on, then the disposal, scraps fed in gradually, and water running a few seconds after grinding stops. Don't grind with hot water, and never pour grease or fat down any drain; InSinkErator says it can build up in pipes and cause blockages. Keep out clam and oyster shells, glass, china, plastic, metal, hot liquids, paint, solvents, and household chemicals, and large amounts of eggshells or fibrous scraps like corn husks. The rest depends on the model; InSinkErator's food list recommends bones, celery, and corn cobs only for its Advanced series, so check your manual. Leave the stopper in when it's off, keep rags, paper, and aerosol cans away from it (a fire hazard, the manual says), and check for drips; a leak sensor under the sink catches slow ones.

Frequently Asked Questions

Why is my garbage disposal humming but not working?

Typically a jam, Moen says: the motor has power but can't turn. Cut the power, work the hex wrench in the bottom until it turns freely, remove any object with tongs, and press reset. Don't keep flipping the switch.

Where is the reset button on a garbage disposal?

On an InSinkErator, it's a small red button on the bottom that drops about a quarter inch when tripped. Moen's is near the bottom, opposite the power cord. InSinkErator's EZ Connect, Builder Series, Amana, and ES units reset themselves after cooling for up to 20 minutes.

Can I use a chemical drain cleaner in a garbage disposal?

No. InSinkErator and Waste King say never to put caustic drain cleaners in a disposal, and Moen says lye or chemical drain cleaners seriously corrode its metal parts and void all warranties. Plunge instead, or call a plumber. If someone already poured one in and the sink hasn't drained, don't run the disposal or plunge: Drano says its gel may splash back if the disposal is turned on over a drain that hasn't cleared, and to consult a plumber.

Why won't my dishwasher drain after a new disposal was installed?

Check the knockout plug. InSinkErator's disposals have a plug inside the dishwasher inlet that has to be knocked out before the hose is connected; its manual warns that if it isn't, the dishwasher may overflow.

The Bottom Line

Cut the power first and never reach in. Silent: press reset, then test the outlet and check the breaker and GFCIs. Humming: free the jam with the hex wrench and reset. Whirlpool but slow: plunge the drain line. Tighten a leaking connection; water through the unit itself means warranty service or a new disposal. A dead outlet, repeated breaker trips, or hardwired wiring belong to an electrician.

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