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How to Fix a Garbage Disposal That Hums (4 Tips)

man removing the garbage disposal unit

A garbage disposal is a great tool, but it can be frightening when it starts humming, especially if it also stops working. If you have been having problems with your garbage disposal, keep reading as we list several tips to help you get it working properly. We cover doing diagnostics, cleaning, unjamming, and resetting your machine and discuss items that you shouldn’t put in the disposal system.

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The 4 Tips on How to Fix a Garbage Disposal That Hums

1. See If There Is a Jam

A humming garbage disposal is more common than you might think, and one of the most common causes is a piece of food that jams the blade and prevents it from moving. The struggling motor produces the loud humming sound that you hear, so you should shut it down quickly to prevent damage. Freeing the jam will help it run normally again.

A plumber laying under a house hold sink working on a garbage disposal
Image Credit: David Spates, Shutterstock

 

How to Check if There Is a Jam:

  • Turn off the garbage disposal, and unplug it so it won’t accidentally turn on while you are working on it.
  • Use a bright flashlight to help you see down into the drain to see if something is blocking the blades.
  • If you see something jamming the blades, remove it. A pair of long bent nose pliers can help you reach down into the drain to grab the item and pull it free.
  • Plug your garbage disposal system back in.
  • Test the system to see if it works and if the hum is gone.
  • If the hum is gone, allow hot water to run down the drain to help clean and rinse off the system.

2. Manually Rotate the Grinding Plate

If you are unable to see a jam, but the hum is still occurring, you will need to manually rotate the grinding plate. In many cases, grease and grime can build up on the blades, preventing them from turning correctly, so manually rotating the blades will help you clean them off.

man checking garbage disposal
Image Credit: DUO Studio, Shutterstock

How to Rotate the Grinding Blade:

  • Shut down your garbage disposal and unplug it.
  • Grab the Allen wrench that came with your unit. If you can’t find it, you will need to locate an appropriately sized Allen wrench, which is usually ¼ inch, but it can vary.
  • Place the wrench on the head of the bolt.
  • Carefully turn the bolt back and forth steadily.
  • If the bolt doesn’t turn at all, it might signify a serious internal problem that warrants a call to a professional repair technician.
  • You manually rotate the grinding plate as you turn the bolt back and forth, which can knock off caked-on debris. Use long bent nose pliers or a pair of tongs to remove loose debris from the plate.
  • With the plate clean, remove the Allen wrench and plug the garbage disposal back in.
  • Test the garbage disposal to see if it still hums.
  • If the hum is gone, let hot water run down the drain to rinse off the system.

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3. Reset the System

If your garbage disposal is still not working, one more option you have is to reset the system. Most garbage disposal systems have a reset button. Find and push it. Give the garbage disposal another try to see if the reset helped remove the hum.

woman cleaning the water leakage in garbage disposal unit
Image Credit: mariakray, Shutterstock

4. Call a Professional

If these tips and tricks didn’t work to eliminate the hum, there is a good chance that an internal problem is causing it and not a food jam or grease buildup, so we recommend calling a qualified technician to have a look. They will be able to diagnose the problem and fix it without voiding the warranty.

Garbage disposal
Image Credit: Minerva Studio, Shutterstock

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How Can I Keep My Garbage Disposal System Running Properly?

We recommend that you avoid putting these foods down the drain in order to prevent your garbage disposal system from clogging up.

  • Banana peels are difficult for your garbage disposal system to grind up, and they frequently cause jams, which can put wear and tear on your system even if they are easy to remove.
  • Potato peels are starchy foods that can create a buildup on your blade that can slow it down and jam it up.
  • Grease will stick to the grinding blade, slowing it down and causing it to jam up.
  • Pasta is a starchy food that can create a buildup on the grinding blade. It can also grow in the presence of moisture, which might cause it to clog the blade and prevent it from spinning.
  • Bones are difficult to grind and can dull your blades, so not putting them down the drain is best.
  • A garbage disposal system can grind coffee grounds into tiny particles that will easily stick to the grease and other materials in the drain, leading to a buildup that can clog your blade.
  • Eggshells seem like they are easy to grind up, but they can dull and clog the blades, so it is best to avoid putting them down the drain.
  • Celery is a popular food that is too tough for most garbage disposal systems to grind up effectively.

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Summary

In most cases, a loud humming sound coming from the garbage disposal is the result of food clogging up the blades and preventing them from spinning. Shutting off the machine, unplugging it, and using a flashlight to find the clog and a pair of long bent nose pliers to remove it will get your system running like new in just a few minutes. If the noise is due to a buildup of grease and grime preventing the blades from spinning freely, manually rotating the ground plate can help you clean it up so it works correctly. In some cases, the system might overheat, and a press of the reset button will get it working again, but if all else fails, you will need to call a professional to ensure that there is no internal damage preventing the machine from working.


Featured Image Credit: DUO Studio, Shutterstock

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