What Happens If You Leave A Garbage Disposal On? [6 Issues]


Distractions happen in life, and sometimes things can be left on, as you tend to do other things.

Ideally, you should never leave a garbage disposal while it is operating, but if you do, you may notice it stops working or working well.  

When you leave a garbage disposal on for too long, it likely will turn off automatically. Even if it does not, the motor or other parts could wear out, or the unit could become overloaded, causing it to overheat or smoke. In most cases, you’ll need to reset the appliance. In other cases, you may run the risk of injury, fire, or need to replace parts prematurely.

6 Effects Of Leaving On A Garbage Disposal For Too Long

The following effects could potentially occur if the garbage disposal is left on.

1. Disposal Needs To Be Reset

Generally, garbage disposals have safety features that force them to turn off due to electrical issues, overheating, or if they are left running for too long. Refer to your user guide for more information about this.

A button, typically red, will pop out from the unit under the sink, turning off the appliance. 

To address this, do the following:

  1. Turn the disposal switch off (typically located near the sink, above the counter).
  2. Press the red button to reset the disposal. If it will not stay pressed in, wait a few minutes and try again.
  3. Run cold water, turn the switch on, and the disposal should work.  

If the reset button will not stay in or the disposal will not work, make sure the main circuit is not tripped. If that is in place, and it still will not work, it is time to call in a professional.

2. Overheating And Risk Of Fire

The appliance can overheat, tripping the reset button. It may feel hot to the touch, and may not turn back on until it has cooled down and the reset button is pressed.

While rare, if the reset button does not trip, there could be a risk of fire. 

For example, some InSinkErator models of garbage disposals were recalled due to overheating of the power module and outlet.

3. Worn Out Motor

Overusing the garbage disposal will cause premature wear of the motor. You could see some smoking or smell a burnt aroma. 

While unlikely, check for any signs of fire before proceeding. A motor can also become worn if there is a jam or clog, causing it to overwork. 

As a result, the life of the appliance is shortened, resulting in the need for repair or replacement.

4. Dull Blades

Excessive running of the disposal can dull down the blades prematurely. 

As a result, food will not grind down as well, and then the blades will need to be replaced more often.

5. Risk Of Injury

Leaving a garbage disposal on, without monitoring it, can pose a danger to you or anyone accessing the sink. 

If someone puts a dish or silverware into the sink or uses their hands near the opening, they could become seriously injured.

6. Poor Energy Efficiency

Running a garbage disposal longer than necessary uses more energy. 

This makes the appliance not efficiently use electricity, negatively impacting your utility bills.

Running A Garbage Disposal Effectively

The following should be implemented when using your garbage disposal. Refer to your user guide for the specifics related to your brand and model.

Cold Water And Running Time

Run cold water into the disposal before turning it on. Do not use hot water, since this will melt grease, oils, and fats, which will then eventually cool and clog your disposal and connecting pipes. 

If you do not use water, you risk damaging the blades and appliance. Water lubricates the blades, further softens the food as it is ground up, and moves it down into the drain pipe.

Do the following:

  1. Add food waste in small amounts and in small pieces. 
  2. Turn on the disposal for 30-second increments. This should be adequate in grinding up food pieces for drainage. 
    • You should be able to hear the blades grading and then change in sound as the pieces are eliminated.
  3. Continue to run the water for 15 to 60 seconds longer before turning off the disposal switch.

Grind Every Time

Grind the food every time you put something in there. Do not let it build up or else you will need to run the disposal for longer periods or run the risk of clogs if it is overfilled.

If you frequently use your disposal every time to grind, it helps to keep the unit functioning. 

Do not let it go unused for extended periods, as lack of use could cause rust or other deposits to build up on it, shortening the life span.

Maintain The Appliance And Clear Clogs

Maintain, clean, and immediately address clogs to prevent odors and plumbing issues. 

Your user guide will tell you what to do, but generally, a combination of vinegar and baking soda will eliminate odors and effectively remove clogs from your garbage disposal.

You’ll need baking soda and vinegar to do the following:

  1. Pour a ½-cup of baking soda into the disposal opening.
  2. Warm to touch 1-cup of vinegar in the microwave or on the stovetop.
  3. Pour the vinegar into the opening of the disposal.
  4. Allow the fizzy reaction to sit for 10 to 60 minutes.
  5. Run the disposal with tap water to rinse it clean.

This video demonstrates some quick ways to maintain and repair a disposal that has no power, is humming, or needs repair:

Use Disposal Approved Food Waste Only

Garbage disposals can only grind up small and soft pieces of food waste with cold water. 

Cut pieces up into small bits before grinding them. 

Keep silverware and other kitchen items away from the opening.

Refer to your user guide, but the following are general examples of what you cannot grind:

  • Coffee grounds
  • Starchy foods, such as potatoes, rice, pasta
  • Oatmeal
  • Banana peels
  • Onion skins
  • Eggshells
  • Nut and pits
  • Bones
  • Meat
  • Fats and oils
  • Non-food items
  • Harsh chemicals, such as bleach

In Conclusion

Garbage disposals offer convenience in disposing of soft food waste. However, overusing them by running them for extended periods can cause issues.

These issues could include the need to reset the unit, the risk of injury or fire, or the need for repair or replacement. 

By using your garbage disposal for 30-second increments with cold water, in conjunction with maintenance and cleaning, you’ll promote longer longevity and better productivity for your garbage disposal.

Want To Know More About Caring For Your Disposal? Read These:

  1. Garbage Disposal Etiquette
  2. Garbage Disposal Flywheel Stuck
  3. Garbage Disposal Smells Really Bad
  4. Garbage Disposal Jammed With Glass
  5. Garbage Disposal Outlet Not Working

Lisa Burlison

Lisa is a freelance blogger, literacy specialist, teacher, and self-published author with a vast DIY experience. When she’s not writing for PlumbJoe, Lisa enjoys testing homemade cleaners and doing repairs around her home. Her other hobbies include birding and bicycling.

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