How to Fix a Garbage Disposal That Hums or Won’t Turn On

Before you start

Empty the cabinet and keep a flashlight handy. If the sink has standing water, InSinkErator says to let it drain or bail it out first.⁠[2]

Match the symptom to the cause

The sound and the timing tell you where to start. The table follows the order that InSinkErator, Moen and Waste King give in their own troubleshooting pages.⁠[2]⁠[1]⁠[3]

1. 01

   Something is jamming the plate

   Most commonDIYTime: 10 min

   The motor hums but the plate inside won't turn.
   Fix it: Something is jamming the plate →
2. 02

   Overload protector tripped

   CommonDIYTime: 5–20 min

   The motor overheated and shut itself off; it stays silent until reset.
   Fix it: Overload protector tripped →
3. 03

   No power at the unit

   CommonDIY with careTime: 15 min

   A tripped breaker, a dead outlet or a faulty switch keeps the motor off.
   Fix it: No power at the unit →
4. 04

   Clogged drain line

   CommonDIYTime: 15 min

   The disposal runs but water backs up into the sink.
   Fix it: Clogged drain line →
5. 05

   Leak at a connection

   Less commonDIYTime: 20 min

   Water drips from the sink flange, the drain elbow or the dishwasher hose.
   Fix it: Leak at a connection →
6. 06

   Worn-out disposal

   Less commonPro only

   It still hums after the jam is cleared, or water drips from the body itself.
   What a pro does: Worn-out disposal →

It hums but won't grind: clear the jam

Bones, fruit pits, bottle caps and fibrous peels can wedge the plate. Moen warns that trying to run a jammed unit again and again can trip its internal breaker, so stop after the first hum.⁠[1]

1. 01

   Step 01 of 04

   Turn off the switch and the water

   • Time: 1 min

   Flip the wall switch off. For extra safety, unplug the unit or switch off its breaker, as Moen does.⁠[1]

   You'll know it worked when: The disposal can't start while you work.

2. 02

   Step 02 of 04

   Turn the plate from below with a hex wrench

   • Time: 5 min
   • 1/4-inch hex key

   Find the hole in the center of the bottom of the unit. InSinkErator ships a small crank-shaped wrench for it and says a standard 1/4-inch Allen wrench also fits. Work it back and forth until it turns freely.⁠[2]

   You'll know it worked when: The wrench turns full circles in both directions.

3. 03

   Step 03 of 04

   Lift out what caused the jam

   • Time: 5 min
   • LED work flashlight
   • Long-handled kitchen tongs

   Shine the flashlight down the sink opening and pull out any object with tongs or pliers. InSinkErator says to check around the teeth at the edge of the plate.⁠[2]

   You'll know it worked when: Nothing is left on the plate or around its teeth.

4. 04

   Step 04 of 04

   Press the reset button and test

   • Time: 2 min

   Press the red button on the bottom of the unit. Turn on cold water, then the disposal.⁠[2] If it hums again, turn it off and repeat the wrench step; InSinkErator says you may need to repeat the process several times.⁠[2]

   You'll know it worked when: The disposal grinds normally with cold water running.

Some models have no hole underneath. Moen and Waste King turn the plate from above with their own un-jamming wrench or a wooden spoon handle pressed against an impeller, with the power off.⁠[1]⁠[3]

Still not fixed? Next likely cause: Overload protector tripped →

It stopped and went silent: press the reset

Disposals protect their motors with an overload protector, often called the reset button. Waste King says a jammed plate can overheat the motor and trip it, as a built-in safety feature.⁠[3] The button is on the bottom of the unit on most models.⁠[7] The guide to finding and using the reset button covers where each brand puts it.

1. 01

   Step 01 of 03

   Turn the switch off and let the motor cool

   • Time: 5–20 min

   Switch it off first.⁠[7] InSinkErator's manual says some models need up to 20 minutes before they restart.⁠[8]

   You'll know it worked when: The motor housing is no longer warm.

2. 02

   Step 02 of 03

   Press the red button

   • Time: 1 min
   • LED work flashlight

   A tripped button sits about a quarter inch lower than normal. Press it gently. If it won't stay up, wait 10 minutes and try again.⁠[7]

   You'll know it worked when: The button clicks and stays in.

3. 03

   Step 03 of 03

   Run cold water and test

   • Time: 1 min

   Turn on cold water first, then the switch. If it trips again soon, look for a jam before you reset it again.

   You'll know it worked when: The disposal starts and grinds.

Still not fixed? Next likely cause: No power at the unit →

It's silent and the button won't help: check the power

If the reset button didn't trip, the power stops somewhere before the motor. Waste King's checklist covers the wire to the unit, the switch, the fuse box and the breaker.⁠[3] If the outlet is dead or the switch is suspect, read why a disposal won't turn on for the full electrical checks.

1. 01

   Step 01 of 02

   Reset the breaker or replace the fuse

   • Time: 5 min

   InSinkErator's first check is the breaker or fuse: switch the breaker fully off, then on.⁠[4]

   You'll know it worked when: The breaker for the kitchen circuit is on.

2. 02

   Step 02 of 02

   Test the outlet with a lamp

   • Time: 5 min

   For a plug-in unit, unplug the disposal and plug in a lamp that is switched on. Flip the disposal switch on and off. If the lamp follows the switch, the disposal needs service; if it doesn't, call an electrician.⁠[4]

   You'll know it worked when: You know whether the outlet gets power from the switch.

A hardwired unit has no plug to test. If the breaker is on and the unit is still dead, InSinkErator says the fault may be in the disposal or in the electrical system.⁠[4]

Still not fixed? Next likely cause: Clogged drain line →

Water backs up into the sink

If the disposal spins but water won't drain, the blockage is usually in the drain line past the unit. InSinkErator checks for a whirlpool in the water with the unit running; if there is one, the drain line is clogged.⁠[5]

1. 01

   Step 01 of 03

   Block the other sink and add water

   • Time: 2 min

   On a double sink, put a stopper in the other drain. InSinkErator fills the sink with four inches of water.⁠[5]

   You'll know it worked when: The other drain is sealed and about 4 inches of water sit over the disposal.

2. 02

   Step 02 of 03

   Plunge over the disposal opening

   • Time: 5 min
   • Flat cup sink plunger

   Press the plunger down slowly and gently, then pull it up fast. Repeat several times.⁠[5]

   You'll know it worked when: The water drains with a rush.

3. 03

   Step 03 of 03

   Flush the line

   • Time: 2 min

   Once the clog breaks, run the water and the disposal for a minute or two.⁠[5]

   You'll know it worked when: Water runs out at a normal speed.

InSinkErator lists grease and caustic drain cleaners among the things never to put in a disposal.⁠[8] If plunging fails, see the clogged kitchen drain guide; a disposal that also serves the dishwasher can also leave standing water in the dishwasher.

Still not fixed? Next likely cause: Leak at a connection →

Water under the sink

Most leaks come from one of three joints: the sink flange on top, the drain elbow on the side, or the dishwasher hose. Moen finds the source with paper towels.⁠[6]

1. 01

   Step 01 of 03

   Run a paper towel leak test

   • Time: 10 min
   • Microfiber towels

   Stopper the sink and fill it with water. Wrap paper towels around the sink flange, the drain elbow and the dishwasher connector, then pull the stopper and check which towel gets wet.⁠[6] If no towel gets wet, InSinkErator says the water may come from somewhere else: the faucet, the sprayer, a water filter or the dishwasher drain hose.⁠[9]

   You'll know it worked when: One wet towel shows the leaking joint.

2. 02

   Step 02 of 03

   Tighten the drain elbow screws

   • Time: 5 min
   • Screwdriver set

   Moen says loose screws on the drain elbow can leak from the metal plate on the bottom.⁠[6]

   You'll know it worked when: The elbow joint stays dry during the next test.

3. 03

   Step 03 of 03

   Check the mount at the sink

   • Time: 10 min
   • Screwdriver set

   InSinkErator checks that the locking ring is turned fully to the right and that the three mounting screws are tight.⁠[9]

   You'll know it worked when: The mount is locked and its screws are tight.

Moen adds that a damaged elbow gasket lets water run down between the shell and the unit, so it looks like a leak from the bottom.⁠[6] A wet dishwasher connector means a loose or worn clamp or connector; Moen says to replace a damaged one and keep it tight.⁠[6] Fit a new gasket for your model rather than reusing a cracked one.

Still not fixed? Next likely cause: Worn-out disposal →

When it's worn out

A disposal that still hums after you clear the jam, or one that leaks from its body with every joint dry, is near the end of its life. Waste King says that if the wiring and electrical parts are intact, the unit may have internal mechanical problems that need replacement.⁠[3] NAHB's 2007 study puts the life of a food waste disposer at about 12 years.⁠[10]

1. 01

   Step 01 of 03

   Switch it off and unplug it

   • Time: 2 min

   Turn the switch off and unplug the unit, or switch off its breaker if it is hardwired.⁠[1]

   You'll know it worked when: The unit can't start while it waits for service.

2. 02

   Step 02 of 03

   Keep the sink and dishwasher idle

   • Time: 1 min

   Use another sink for now. Water from the dishwasher drains through the disposal on many installations.

   You'll know it worked when: No more water runs through the unit.

3. 03

   Step 03 of 03

   Note the model and call for service

   • Time: 5 min

   Find the label on the unit and write down the model and serial numbers. A unit still under warranty goes to the maker first.

   You'll know it worked when: A plumber or the maker's service line has the model and the symptoms.

Still not fixed? See when to call a pro →

Parts and tools for this fix

A flashlight, a 1/4-inch hex wrench and a pair of tongs handle most of these fixes. Gloves help when you work in a tight cabinet.

When to call a pro

Call an electrician for a dead outlet or a breaker that trips again. Call a plumber for leaks you can't stop and for a new unit.

If a jam keeps coming back after these checks, call the maker's support line before you buy parts; Moen's unjam page ends with its consumer support number for that case.⁠[1] Owners of that brand can use the InSinkErator disposal problems guide for model-specific steps.

Frequently asked questions