A humming noise from a garbage disposal that isn’t spinning usually means that power is reaching the motor, but the grinding plate isn’t turning. There are a few common reasons why this is happening, including a problem with the motor, a jammed impeller or a stuck flywheel.
You may be able to fix some of these issues. For others, the best and safest option is repair or replacement by a professional.
Do not repeatedly press the reset button or do anything else that forces the disposal to run because it can damage the motor.
Quick Takeaways
- The most likely explanation for a humming disposal is that the motor has power but isn’t turning.
- A humming disposal is most often caused by foreign objects and food debris.
- You may destroy the motor if you continue to run a jammed disposal.
- You may be able to clear the jam safely with the right tools.
- You might need a professional to repair or replace your disposal if troubleshooting fails.
1. The Flywheel Is Jammed
A flywheel is the small metal plate that spins at a high speed and causes the impellers to break down food into small particles. Items that don’t belong in a garbage disposal but frequently fall into it can jam a flywheel. This includes bones, utensils, fruit pits and fibrous foods, such as celery.
To free a jam, look under the disposal. You’ll see a hole that you can insert a hex wrench into. Turn the wrench in one direction and then the other.
If the flywheel won’t move or there is a leak, you should stop trying to troubleshoot.
2. Something Is Stuck Between the Grinding Plate and Chamber
You may have dropped a piece of jewelry, a utensil or other foreign object down the drain. However, you should not put your hand down to retrieve it because you could you could cut yourself on the blades.
Even with the power off, this is a danger. Instead of your hands, use pliers, tongs or another tool to reach into the drain.
3. The Disposal Motor Has Overheated
An overload protector automatically shuts off your garbage disposal if it’s overheating. This helps prevent your motor burning out.
Overheating can happen because you’ve put too much food into the disposal or food that it can’t easily grind. It can also happen if you aren’t running water when you run the disposal.
You may be able to fix the problem by simply waiting 15 to 20 minutes and then pressing the reset button. Run plenty of water before you start the disposal again, and it may be able to finish the job.
If your garbage disposal repeatedly overheats, your motor may need replacement.
4. The Disposal Is Clogged
In a drain clog, your disposal works normally but there is a blockage further along in your pipes. This can cause water and debris to back up in your sink. If you have a disposal jam, you may hear a humming sound or the disposal might not spin.
If you keep running the disposal when there’s a jam, it can worsen the jam or damage the disposal.
5. The Motor Is Wearing Out
Garbage disposals last an average of 10-12 years. Your motor may be failing if you can’t locate a jam and there is a burning smell or the reset button keeps popping back out.
If your disposal is more than 8 years old or if a repair will cost at least half the price of a replacement, replacing it may be the better option.
6. The Disposal Was Installed Incorrectly or Has Loose Components
If your disposal is vibrating or making strange noises, it might be a loose mounting assembly. Check and tighten the three mounting screws and make sure the snap ring is in place.
Over time, through wear and tear, there may be worn components inside that are making rattling or clanking sounds.
7. The Motor Has Failed Completely
If there is a burning smell or the reset button is tripped over and over, you may be looking at motor failure. Motor failure is also a possibility if you’ve tried troubleshooting without any results.
The above problems as well as frequent overheating may mean the motor has to be replaced.
What You Should Do Before Calling a Plumber
Before you do any troubleshooting, turn off the power. Do not put your hand into the disposal. You can use a flashlight to check for any obstructions in the drain.
Try pressing the reset button one time, and use the hex key underneath the unit to see if there’s a jam. Stop DIY troubleshooting if you can’t find an obstruction, the reset button pops out repeatedly, you notice a crack in the unit or there is a leak.
You should also stop if you’ve tried the basic tips above and it hasn’t helped.
When Should You Replace a Garbage Disposal?
Replacing the entire garbage disposal may be a better option than repair if your unit is more than 8 years old, the motor is burned out or there are leaks. You may also want to opt for replacement if the jams or humming keeps happening. Replacement may be the most cost-effective solution if the repair is an expensive one.
Frequently Asked Questions
Why is my garbage disposal humming but not working?
This can be caused by something that is stuck in your disposal and jamming the parts, such as the flywheel or the grinding plate. The problem might also be with the motor, loose parts or an incorrect installation.
Is it safe to press the reset button multiple times?
No, pressing the button multiple times can start a fire or destroy the motor.
Can I fix a humming garbage disposal myself?
You may be able to fix it yourself if the problem is something caught in the disposal. However, for more serious issues, including problems with the motor, you should contact a professional.
Does a humming garbage disposal always need to be replaced?
No, there could be a quick and easy fix, such as removing something that is stuck within the machinery. However, there are situations in which the humming is the symptom of a bigger problem that requires replacement.
Get Your Garbage Disposal Working Again
If you’ve done some basic troubleshooting and your garbage disposal’s still humming or the motor has failed altogether, Benjamin Franklin Plumbing can help. We perform garbage disposal repair throughout the Bradenton area.
We’re known as “The Punctual Plumber®” because you’ll never have to sit around waiting for us. Contact Benjamin Franklin Plumbing today to get your garbage disposal working like new.