How to fix a clogged garbage disposal
How to fix a clogged garbage disposal
Key takeaways
You can fix a clogged garbage disposal yourself; a leaking disposal should be replaced by a plumber
Never reach into the disposal’s chamber with your hand; use tongs to safely remove any clogged material
Avoid putting stringy food waste—such as celery, artichokes, or corn husks—in a disposal
Rarely seen, often heard, and always on call to chew up food waste, garbage disposals are the hardest-working appliances in your kitchen. While garbage disposals are built to last 10 to 12 years, according to a National Association of Home Builders (NAHB) study, they also put up with a lot of use—and abuse—that causes clogs and jams.
Most homeowners don’t realize how essential a garbage disposal is to daily life, until they flip the switch to clean up a kitchen sink full of scraps and nothing happens. “Nine times out of 10 the disposer is overloaded because something is lodged inside or the unit is corroded from lack of use,” explains Michael Keleman, manager of environmental engineering for InSinkErator.
You can call a professional plumber to repair or replace the appliance, or try to fix it yourself. Here’s how:
DIY facts
Skill level: Easy
Cost: DIY $0; hiring a pro $150
Repair time: 2 hours
Tools needed:
¼-inch hex wrench or Allen wrench
Channel-lock pliers
Flashlight
Tongs
Wood broom stick or toilet-plunger handle
How a garbage disposal works
Garbage disposals are designed to catch and grind up food waste that falls into the sink drain. When you turn them on, a rotating disk (or flywheel) at the bottom of the unit starts spinning. The disk has “teeth” called impellers that work like a cheese grinder to shred food scraps into pieces small enough to pass through holes in the flywheel. Running cold water then flushes that waste down the drain.
Learn how a garbage disposal works. Video: InSinkErator
Troubleshooting the problem
Because it’s in the waste management business, a garbage disposal often becomes caked with gunk and bacteria that brings its work to a halt. The good news: Fixing a garbage disposer is often a simple home repair.
Caution: Before working on a garbage disposal, unplug it from the receptacle under the sink, or turn off the circuit breaker at the main panel. Never reach into the disposal with your hand. Use tongs to remove objects stuck in its grinding chamber.
Here the 3 top things that can go wrong and how to troubleshoot them.
1. Disposal doesn’t turn on
A simple electrical reset usually solves this common problem. Here’s how:
Make sure the disposal is plugged into the under-sink receptacle and that the circuit breaker has not tripped off.
Check the red reset button on the underside of the disposal. If it popped out, push it back in until it clicks and stays retracted.
Turn the power back on, run water, and turn the disposal on. If it runs, it’s reset.
2. Disposal makes a humming sound
If the unit doesn’t grind when you turn it on, you probably have a jammed garbage disposal. This happens when an object gets stuck between the impellers and the wall of the grinding chamber. To fix it, follow these steps:
Turn off power to the disposal.
Find the 1/4-inch hex socket in the bottom of the motor housing. Place a hex or Allen wrench in this socket and turn it back and forth. This turns the plate that the impellers are mounted on. When the wrench turns freely in both directions you’ve loosened the jam.
Look inside the disposal with a flashlight for anything that could have caused the jam. Remove it with a pair of tongs.
Restore the power, run cold water, and turn the disposal back on. If there’s no hum, just the normal clatter, it’s fixed.
3. Disposal is filled with standing water
If water is collecting in the grinding chamber, there’s probably a blockage in the unit or drain pipes. The easiest way to drain this water and find the blockage is to loosen the disposal drain-pipe connections to the house plumbing.
Here’s how to fix it:
Place a bucket under the P-trap—the U-shaped pipe that holds water to prevent sewer gases from coming up through your drain. The bucket will catch any water that may spill out in the next step.
There are two large slip nuts on each end of the trap. Loosen the uppermost slip nut (at the top of the trap). Use channel-lock pliers if it’s too tight to loosen by hand. If water releases after opening the trap, it means the blockage is inside the trap.
Loosen and remove the slip nut on the other end of the trap. The entire P-trap should slip off the pipe that leads to the disposal and house plumbing drain pipes. Dump any water or waste that accumulated in the trap into the bucket.
Clean out the trap of any remaining waste, so water flows through it clog-free.
If water remains in the unit after opening the P-trap, the disposal’s drain may still be clogged. Here’s what to do next:
Loosen the slip nut at the top of the house drain pipe that’s connected to the disposal drain pipe.
Slide the house drain pipe off the disposal’s drain pipe.
Reach into the disposal’s drain on the side of the unit and feel for a clog. If you’re lucky, you can pull most of the clog out with your fingers.
For tougher clogs, use a piece of coat hanger or stiff wire to loosen the debris, then pull it out.
If you don’t feel the clog or can’t remove it, you’ll need to remove the disposal drain pipe (the pipe connecting the disposal unit to the P-trap). Here’s how:
Remove the 2 screws on the side of the unit that hold the disposal drain pipe in place.
Pull the pipe away from the disposal to expose the drain opening and remove the clog.
Then, reassemble the drain pipe on the side of the disposer, followed by the rest of the drain pipes, including the P-trap.
With a bucket still under the P-trap (in case of leaks), run cold water into the unit and turn it on to clear any remaining waste. If water is leaking from any of the pipe joints, further tighten the slip nuts. No leaks? That’s it, you’re clog-free.
Dos and don’ts of using a disposal
Garbage disposals can grind almost anything if they’re used properly. “Most people wait till they have a sink full of scraps before running the disposal and that can cause an overload,” warns Keleman. Here’s the right way to run a disposal:
Turn the water on first
Then, turn on the disposer
Slowly add food waste
Leave the disposal running for a few seconds after all the waste has been added.
Keep your disposal out of trouble with proper use and maintenance:
DON’T overload the unit. If it’s too full, the disposal can’t grind the waste small enough to flush easily.
DON’T put coffee grounds, bones, pasta, oatmeal, nuts, potato peels, eggshells, or stringy foods such as celery, corn husks, and artichokes into the disposal. Remember, whatever you put down there still has to be ground into a consistency that can drain through the small flywheel holes.
DON’T put fats, oils, or grease into a disposal (FOG, for short). The same fats that clog the arteries of your body can also plug up a disposal’s system, warns Keleman.
DO run the disposal only while also running cold water. The force of cold water helps chop up food waste. Cold water also keeps grease in a more solid form as it passes through the drain pipes. Hot water should never be used while running the disposal. Fats initially melted by hot water can solidify further down the drain and cause a blockage.
DO clean your disposal every other week by grinding up 1-2 cups of ice cubes. Run the disposal for 10 seconds to allow the cubes to bounce around in the grinding chamber, removing debris from its walls.
DO run your disposal for a few seconds everyday. When disposals are not used regularly, the metal blades can corrode and cause jams or malfunctions.
DO keep the disposal smelling sweet by occasionally grinding up lemon or orange peels under cold water.
Read the disposal’s product manual before using or fixing the unit. Garbage disposals come with different motor strengths, some of which have enough horsepower to grind most food scraps. Brands such as InSinkErator, for example, claim they can grind peach pits, bones, or even an entire Thanksgiving turkey carcass.
When to replace a garbage disposal
There are 2 signs it’s time to replace your garbage disposal:
When the garbage disposal leaks
When it takes more than one push of the red reset button or main panel breaker to keep the disposal running.
Both these conditions signal an underlying problem with the unit. Your plumbing may also be contributing to the issue if it’s old, improperly sloped, or there’s root intrusion in the pipes, explains Keleman. These more complex tasks are better left to a professional plumber. Learn how to find a good plumber.
When you need a garbage disposal repair pro
A plumber typically charges $150 per hour to troubleshoot and repair a garbage disposal. An appliance service professional will charge about $400 labor cost to replace a broken unit with a new garbage disposal. A new unit can run from $100–400, depending on horsepower and other features.
Find a good plumber
Tell us about your garbage disposal problem, and we’ll connect you with local pros.