Here’s Why Your Garbage Disposal is Completely Messed Up

garbage disposal troubleshooting

Considering the use and abuse your garbage disposal endures, it really shouldn’t be surprising when it breaks down. However, many times there’s nothing seriously wrong with it. Before you rush out and buy a new unit, try troubleshooting and repairing your disposal instead. Most of the problems you’re likely to encounter are easily solved with a few tools and a little bit of time.

How a Garbage Disposal Works

A garbage disposal is a fairly simple appliance. Think of it as a mechanical digestive system of sorts, mounted underneath your sink. Food and food waste passes through the mouth (the sink drain hole) into the stomach (the upper chamber of the garbage disposal), which is called the upper hopper chamber.

Before servicing your garbage disposal, turn off the power supply. Even with the power off, never place your hand inside your garbage disposal.

When you flip the switch to turn on your garbage disposal, the motor inside the lower hopper chamber spins a flywheel, causing attached impellers to rotate at almost 2,000 RPM. These impellers throw the disposed food against a shredder ring, resulting in ground-up food waste.

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Running water then flushes the pulverized matter out through the discharge outlet to either the sewer system or septic tank. Built-in dishwashers usually connect to the drain line through an inlet located at the top of the hopper. Water and waste from each load of dishes therefore runs into the disposal and out the waste outlet on its way to the sewer or septic tank. So, a problem with your garbage disposal may actually impact your dishwasher as well.

Locating the Reset Button and Flywheel Turning Hole

If you’re not already familiar with your garbage disposal, don’t stop at understanding how it works – take the time to examine it and locate the various parts you may need to service. Besides the upper and lower hopper chambers, which form the garbage disposal unit body, find the waste line and the dishwasher drain line entering the unit, if applicable. (If you don’t have a dishwasher draining through your disposal, this line is missing; the dishwasher drain inlet is a punch-out hole that’s readied during installation.)

Take a look at the underside of your garbage disposal. You should see a cover plate, an electrical reset button and a manual flywheel turning hole. (In a few models, the reset button may be located on the front of the disposal instead.) The reset button and flywheel turning hole figure prominently in certain repairs. Turning the flywheel manually can break it free when it becomes jammed – assuming you remove the matter causing the problem first. Hitting the reset button resets the components and allows the unit to work again. See further information on the reset button below.

Safety, Tips and Tools

Before servicing your garbage disposal, turn off the power supply. Even with the power off, never place your hand inside your garbage disposal.

Try gathering your tools before tackling the troubleshooting and repair. This saves time and avoids spreading the mess. You may need one or more of the following items:

  • Flashlight or other portable light
  • Pipe wrench
  • Screwdrivers – both flat-head and Phillips
  • Rigid wire (such as a straightened coat hanger) or drain auger (snake)
  • Turning tool – offset wrench, Allen wrench or broom handle
  • Bucket or pan
  • Plumber’s putty

Never use a chemical drain-cleaning product in your garbage disposal. Doing so may damage the machine and void any warranty it may have.

Avoid using bleach in your garbage disposal as well. Bleach is hard on the rubber components, such as the gaskets that seal connections and rubber hosing. Over time it will eat away the rubber.

If a major problem arises that proves beyond the scope of these simple problems and repairs, you may be better off just getting a new garbage disposal.

Troubleshooting a Garbage Disposal: Diagnosis by Symptom

When you’re troubleshooting any appliance, every detail is a clue that, pieced together, helps pinpoint the potential cause. Even within a given symptom, you may find more than one potential cause. Accurate diagnostics therefore rely on good observation of every detail.

Garbage Disposal Won’t Turn On – Makes No Noise

When your garbage disposal doesn’t run and doesn’t make a sound, there’s an electrical supply problem. Try running through these easy repairs:

  • Make sure it’s plugged in. As obvious as it may seem, with the outlet located under the sink, it’s easy for it to become unplugged.
  • Press the reset button. If it’s popped out, something tripped the reset button and simply pushing it in may fix the problem. Note: If it trips again, something is wrong, so don’t simply keep resetting the unit.
  • Check the circuit breaker on which the garbage disposal runs. If it has tripped, reset it and try using the garbage disposal once more. (Again, if the circuit breaker continues to trip when using the garbage disposal, there’s a deeper problem. Don’t continue to simply reset it.)
  • If the reset button is not tripped, it’s plugged in and the circuit breaker is on, the problem may be a bad switch, a bad electrical outlet, or more likely, a bad garbage disposal unit. An electrician or other knowledgeable individual can test the switch and outlet with a multimeter. If they test live, the disposal’s motor is bad and the best option is replacing the garbage disposal.

Garbage Disposal Won’t Turn On – Makes a Humming Sound

If your garbage disposal makes a humming noise but won’t actually work, immediately turn it off. By design, the reset button should trip before it allows the motor to overheat. Still, don’t take any risks. Chances are good that the flywheel is jammed. Matter is likely trapped between the impeller and shredder ring or around the flywheel itself. A bound-up garbage disposal is unlikely to fix itself. Usually the fix is simple:

  • Turn off the power to the unit at the electrical service panel and unplug it to ensure the unit can’t turn on. Double check by flipping the switch to see if it works.
  • Using the offset wrench that came with your garbage disposal or a suitable Allen wrench, free up the flywheel manually. Insert the wrench into the flywheel-turning hole and turn clockwise until you feel the flywheel turn freely.
  • Substitute a broom handle or similar object for the wrench and work from the top of the unit in a pinch. Enter the garbage disposal from the kitchen drain, pushing the tool down to the bottom against an impeller. Leverage the tool to break free the flywheel. When you feel the flywheel turn freely, the problem is solved.
  • Turn on the power to the unit, then press the reset button if necessary.
  • While running water down the drain, quickly turn your garbage disposal on, then off, and on again, repeating several times. These short bursts of spinning, in combination with the water, will hopefully rinse away the matter that caused the jam.

Garbage Disposal Runs – Water Doesn’t Drain or Drains Slowly

Sometimes it’s not that the disposal isn’t working, but that nothing’s moving. When the water begins to back up in your sink even as the garbage disposal makes its racket, you may have a clog. Don’t get intimidated now – fixing the problem is generally easy:

  • Turn off the power to your garbage disposal. Unplug the unit as well. Test to ensure it won’t work before proceeding.
  • Reach into the garbage disposal, using pliers or tongs, and remove all excess food and matter. Large food bits or foreign objects in particular are likely to clog the outlet hose and cause water to back up. Simply uncovering the hose may fix the problem.
  • Test your garbage disposal to see if the clog is gone. Make sure your hands or tool are no longer in the drain. Turn on the water, then the disposal, to see if the water drains out properly.

If the water still backs up in the sink, your clog is a little deeper than the disposal. Try the simplest solutions first:

  • Dip out as much water as you can before proceeding. Pour it down a functioning drain elsewhere in the house.
  • Seal off the other drain hole if you have a double sink. Stuff it with a wet rag or, better yet, a solid plug. The point is to obtain an airtight seal once the drain is covered on the disposal side.
  • Use a plunger to break the clog free. Leave just enough water in the disposal side of the sink to cover the rim of the plunger (2 to 3 inches) and rapidly push down on the plunger several times in succession. Pull it completely free of the sink to see if the clog is gone.
  • Place a large bucket or pan under the sink and disposal area if the clog remains. Use this to catch any dripping water during repairs.
  • Disassemble the pipes under the sink, pouring out standing water as you work. Often the clog will be either in the P-trap, the tee where the two sinks join when applicable, or in the disposal’s elbow. Use a stiff piece of wire such as straightened coat hanger or a plumber’s snake to poke through and clear the clog.
  • Reassemble the drainpipes, resupply power to the garbage disposal and test the operation. Turn the water on first. Quickly turn the disposal on and off a few times to help encourage any matter to flush away.

You can also disconnect the discharge drainpipe and look for clogs inside it, or even dismount the disposal unit if you run out of choices. If none of these measures work, the clog is likely deeper in your drain line. Consult a professional plumber for further assistance.

Given proper care and use, your garbage disposal shouldn’t clog. If you have repeated clogging problems or the garbage disposal is old, the blades may be broken. Good blades will grind food up well enough to flow through the drain line. Worn, irregular blades will not.

Garbage Disposal Leaks

Most garbage disposal leaks occur in one of three places. Tackle the problem and stop the moisture before bigger problems – such as mold and rot inside your cabinetry – join the crowd. Always turn off the power to the unit before fixing leaks. Set a bucket or pan beneath the leaking area to catch any water spilled.

  • The Discharge Drainpipe Connection: If the discharge drainpipe leaks, try tightening the bolts that hold it to the disposal. If they are already tight or if the leak continues, remove the bolts to detach the drainpipe and replace the rubber gasket that seals the connection between the pipe and unit.
  • The Dishwasher to Disposal Connection: Try tightening the clamp that holds the dishwasher drain hose to the dishwasher inlet on the side of the garbage disposal. If it is already tight or the leak continues, replace the entire hose. With age and exposure to very high temperatures, rubber parts easily deteriorate. In addition, the hose running through the cabinet under the sink is vulnerable to damage.
  • The Sink Flange to Disposal Connection: Turn the entire disposal unit counterclockwise to loosen it from the mount flange that holds it to the sink. Tighten the three mounting bolts that run vertically between the flange and mounting bracket. Bumping the unit can loosen these, leading to leaks. If, on the other hand, the bolts are already tight, try adding plumber’s putty between the sink flange and the sink. Circle the entire flange to create a good seal. Next, tighten the mounting bolts to secure it and wipe away any oozing putty. Check for leaks before putting your tools away.

Proper Care and Use of Your Garbage Disposal

A repair technician can sharpen the blades, replace the motor and perform other in-depth repairs on your garbage disposal. However, it may be much less expensive to simply replace the unit when something goes wrong and start fresh again.

Unless you take care of your new disposal, it won’t last long either. Follow some simple tips to keep your disposal working longer.

  • Don’t use chemical drain cleaners or bleach. Avoid all harsh chemicals that may deteriorate the rubber components or other parts of the disposal.
  • Throw away potato peelings instead of using your garbage disposal. Ground-up potatoes form a starchy paste that clings to parts and may clog your unit or the drain.
  • Coffee grounds and eggshells are also hazardous to your disposal. The small, granular consistency creates a sludge that quickly builds up inside the unit and your drainpipe.
  • Don’t put overly fibrous materials and bones in the disposal.
  • Avoid non-organic materials such as plastic, metal, glass or rubber.
  • Run plenty of water when using your disposal. Start the water before turning the disposal on and allow the water to run a bit after shutting it off.
  • Use cold water instead of hot. Hot water melts fats, which can later solidify down the drain.
  • Don’t overfill the unit. Push a few items at a time into the garbage disposal and run it longer instead.
  • Use a wooden spoon to push food into the disposal, and tongs or pliers to grab items out. Never get your hands near the unit even when it’s turned off.
  • To remove built-up sludge inside your garbage disposal, toss in some ice cubes and a cup of rock salt. Run for a few seconds, then rinse.
  • Sharpen the blades inside your disposal by throwing in ice and running for a few seconds.
  • To deodorize your disposal, grind up lemon peels. Alternatively, try a couple handfuls of baking soda, tossed down the disposal drain, followed with a half cup of vinegar. Allow it to sit in the disposal with the power off. When the foaming stops, rinse to flush.

By following these smart practices, your garbage disposal may last much longer than 10 years. You will have fewer repairs as well. Taking the time to do things right can save you time and money.