So, you’re wondering how to fix the garbage disposal. Fear not, we have some handy solutions for common problems, informed by plumbing professionals. But before you do anything, you must learn one rule. Let’s call it Rule No. 1: Never stick your fingers into your garbage disposal. If you’re wondering about Rule No. 2, don’t. Refer to Rule No. 1. Never forget this rule, dear reader, and you’ll be sure to retain the healthy functionality of all your precious digits. Now that you know the rule, you’re ready to start learning a little more about how to unclog a garbage disposal, debris removal, cleaning the garbage disposal, troubleshooting problems and more.
How it works
Don’t let the Sarlacc pit of kitchen appliances intimidate you. It’s not a super-complicated device, and it has a power cord like any other. Mounted under the sink, you’ll find the humble garbage disposal. It works when a disc (the impeller plate) spins its blades to chop up your food waste inside your drain, beneath your sink. Not so complex, right?
There are a few variations on this setup. Batch-feed units require a cover for the blades to engage. Continuous models operate with a switch. An air-switch design activates with air. All these variations on the same theme receive power via an outlet typically situated under the sink, near the unit itself. Even for the best models, however, it’s not uncommon for garbage disposals to fail and require some troubleshooting, which we’ll get to shortly. Meanwhile, sit tight, and remember Rule No. 1.
If you’d like to prevent problems before they occur, you might want to follow some garbage disposal best practices. They’ll help you keep your garbage disposal unit running strong and reliably. Keeping the blades sharp is as easy as grinding up a cup of ice on occasion. Run the system often and regularly to keep it from gathering or retaining any gunk, rust or corrosion. Grind up lemon peel pieces with a half-cup of vinegar or baking soda and cold water for a regular refresh and deodorizer.
Make sure you flush food scraps with cold water because you want to keep any food grease from liquifying in hot water and clogging up your drain. While you’re at it, take it easy with the food debris, and don’t cram it full. A good rule of thumb is to grind about only a cup of organic material at a time. Cleaning the garbage disposal can easily be accomplished by regularly running the unit with cold water and dish soap for about a minute.
Items to avoid
Remember, nothing should go into a garbage disposal except organic biowaste from food, and this includes chemical drain cleaners, which are packed with toxic chemicals, could damage the unit, and might even void your warranty. This also includes items that should be obvious but have been seen in homes where someone clearly had a brain drain, such as cardboard, aluminum cans, paper and yard waste, plastic toys, wood chips, charcoal and marbles.
There are also a few food or food-adjacent items that you’ll want to avoid to keep your system running smoothly for the long haul. Even if food is organic and will chew up easily, it’s not always good for the health of your drain and disposal or for reliable clog prevention. If you remain unsure about what’s OK to put in there, here’s a list of questionable items to avoid grinding in your garbage disposal (some might surprise you):
- Coffee grounds and eggshells
- Cooking fat, grease and oil
- Large meat portions
- Rice, pasta and potato peels
- Shrimp and seafood shells
- Bones, seeds, cores and raw vegetables
Troubleshooting: No power
OK, it’s time for that troubleshooting we promised earlier. If you experience a garbage disposal breakdown and are determined to try fixing it yourself, first gather a few tools, like sets of screwdrivers, wrenches and hex keys. You also may want to grab a garbage disposal wrench if you don’t have one, some needle-nose pliers, various fastener clamps, some clean rags, a headlamp, a handheld flashlight for backup and a bucket. If you have no power, meaning your garbage disposal won’t turn on when you flip the switch, and you aren’t hearing any humming from the motor, then there’s an electrical problem preventing the unit from getting power. Here are eight steps to help you diagnose and correct this problem:
- As any skilled tech-support person would ask first, is the unit plugged in?
- If it’s plugged in, hit the garbage disposal reset button on the bottom of the unit.
- Still no power? Check the circuit breaker in your main electrical panel.
- If cycling the reset as well as your circuit breaker fails, it’s the wiring or a bad disposal.
- Turn off the power at the breaker box to ensure the unit is not getting power.
- Take apart the power switch, inspect the wires, and tighten any loose connections.
- Cycle the power again. No luck? Replace the switch itself and cycle the power one more time.
- At this point, if you’re still not getting power, you will need to replace the disposal.
- Troubleshooting: Humming
If your garbage disposal is humming, but the internal parts aren’t spinning, it’s likely the impeller is stuck. Usually, this causes the reset button to pop out or prompts the breaker to flip. You’ll want to address this problem quickly before the motor has a chance to burn out. The common problem here is something has become stuck in your garbage disposal. Quickly refresh your memory of Rule No. 1, then take these next steps:
- Cut the power at the breaker box as well as at the wall switch to make double-sure it’s off.
- Use your garbage disposal wrench in the hole in the bottom of the disposal.
- Turn the wrench clockwise to loosen the impeller until you can feel it turning.
- Lacking the wrench, try a wooden-spoon handle in the disposal to unstick the parts.
- Peer into the drain with your light(s) to spot and remove the foreign object with pliers.
- With your impeller newly freed, flip the breaker back on, but leave the power off to the unit.
- Go back underneath the sink and hit the red reset button to reset the parts in the unit.
- Run cold water down the drain, and switch the disposal off and on a few times.
- If this doesn’t get you back in business, you need to call a professional.
If you experience something similar to the two scenarios described above yet find your situation compounded by the arrival of smoke, that means your motor is nearly kaput — or you’ve managed to burn out your home’s electrical circuit. Either unpleasant scenario can be fixed. Turn off all power to the unit and try these steps:
- Check other appliances on your kitchen’s electrical circuit to make sure it’s only the disposal.
- Disassemble the cover cap at the bottom of the garbage disposal under the sink.
- Look for burned wires and replace any you find, including any damaged wire insulation.
- Reattach all new wiring into the proper places with the same connections.
- Replace the lower cover, turn the power back on, and see if your disposal works.
- If your disposal still isn’t working, or if you can’t change wires, it’s time to call a pro.
A leaking garbage disposal is no fun for anyone, and it can be tough to pinpoint the exact location of a leak. One common spot for leaks is the hose between the dishwasher and disposal. Tighten the hose clamp that connects the dishwasher inlet to the disposal, or replace the hose if you must. Another spot that can leak is the discharge hose from the disposal to the drain. Replace the gasket seal between the pipe and the disposal, then tighten the bolts holding the pipe.
If your leak involves a third common area for leaks — the sink flange connecting the disposal to the sink bottom, which the disposal’s repeated vibration can loosen — follow these steps:
- Cut the power to the unit at the breaker box.
- Where the unit meets the sink, turn the disposal counterclockwise to loosen it.
- There are three bolts that mount and hold the flange to the sink. Tighten these.
- If the bolts are tight, you need a new seal of plumber’s putty. Loosen the bolts.
- Squirt a new seal of putty in between the sink and flange, in a complete circle.
- Tighten the bolts into the new seal until the putty is forced out, then wipe it away from the edge.
- Reinstall the unit, and restore the power at the breaker box. Test and check for leaks.
- If any of these three leak-fix methods fails, it’s time to call in a professional.
Troubleshooting: Slow drain
A slowly draining garbage disposal usually points to a clog, which can usually be fixed by taking apart the drain trap and discharge pipe, then digging out any obstructions holding up the water flow. Here are the steps you can follow to accomplish this fix:
- Remove the bolts that attach the discharge pipe to the disposal.
- Disconnect and remove the drain trap and discharge the drainpipe.
- Look for any objects or clogs that could be causing the blockage and remove them.
- If you find no clogs, there’s probably one in the drain line going to the wall.
- Clear the drain-line blockage with a sink auger.
- Put the drain trap back together with the discharge tube on the side of the disposal.
- Turn on the water, then turn on the disposal and make sure water runs freely.
- If you’re still having problems, call a professional.
Replacing a garbage disposal and the cost of a garbage disposal
Replacing a garbage disposal — your last resort after trying all these troubleshooting DIY fixes — isn’t all that difficult or even prohibitively expensive. The average unit costs between $100 and $300, and if you’re handy with a wrench, you can likely install it yourself without much trouble. If you have any issues, you can refer back to this article for tips on how to proceed.
For more tips on how to prevent garbage disposal trouble, consider further reading on common plumbing mistakes, or browse our survey on whether Americans know how to take care of their kitchen appliances. If you’d like to learn more about how our Cinch home protection plans can help you handle home repairs, we have plenty of information to share.
The information in this article is intended to provide guidance on the proper maintenance and care of systems and appliances in the home. Not all of the topics mentioned are covered by our home warranty or maintenance plans. Please review your home warranty contract carefully to understand your coverage.