Why Is My Garbage Disposal Humming?
Troubleshooting Common Problems With 6 Easy Repairs
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Reviewed by Richard Epstein
A garbage disposal humming means that the blades are not turning, which can be caused by a clog, an overheated motor, or even a physical obstruction like a fork or spoon. Many households rely on a garbage disposal to break down a variety of soft and liquid food items, such as citrus fruit peels, which can also help to freshen up the scent of the disposal. Before putting anything into the garbage disposal, ensure it works properly to avoid damaging the blades or the motor.
If your garbage disposal starts to hum when you turn it on, it's important to find out why it is making this noise and how to fix it. Use this guide to learn why the garbage disposal is humming and what you can do to repair the issue.
Warning
Never stick your hand or fingers into the disposal. Always cut all power to the unit and use tongs or needle-nose pliers.
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Obstructed Blades
Cause
A garbage disposal isn't full of razor-sharp blades that can cut and slice through anything. If you or someone else in your home puts any items into the disposal that the appliance is not designed to handle, like cutlery or a child's toy, then it can obstruct the movement of the blades. When the switch is flipped to turn the garbage disposal on, the electricity will still run to the motor, and the motor will still try to turn the blades, resulting in a loud humming sound.
How to Repair
Turn off the garbage disposal and disconnect it from the power source by flipping the associated circuit breaker.
Once the garbage disposal is safely disconnected, use a pair of metal tongs to reach into the disposal and retrieve the object causing the obstruction. Depending on the object, you may need a set of long needle-nose pliers to grip the item and pull it out of the disposal.
After pulling the item out, reconnect the disposal and run cold water into the sink.
Turn on the disposal and verify that it is working properly. Remember that if you try to use an obstructed disposal, the motor may burn out.
Clogged Disposal
Cause
Similar to putting a fork or spoon into the disposal, if you regularly add food or items the garbage disposal cannot handle, like coffee grounds, hot grease, or clam shells, a clog can form that prevents the blades from moving. The motor still receives electricity when the switch is turned on, but because the blades are stuck, the disposal does not work. Instead, it creates a low humming sound that indicates there is a problem.
How to Repair
Turn off the garbage disposal and disconnect it from the home's power by flipping the associated breaker switch.
Insert an Allen key into the hole at the bottom of the garbage disposal and gently rotate it back and forth to loosen the clog. Run cold water to lubricate the inside of the disposal and break up the clog.
Use a flashlight to confirm that the bulk of the clog has been removed.
Reconnect the unit and turn the garbage disposal back on to verify that it operates freely without humming.
Disposal Needs to Be Reset
Cause
Garbage disposals come with a reset switch typically located on the bottom of the unit. If you have made sure there aren't any problems with clogs or obstructions and the garbage disposal continues to make a humming sound when you use it, you may have to reset the disposal.
How to Repair
Inspect the reset switch on the bottom of the garbage disposal to ensure it isn't worn out or faulty.
Press the switch to reset the garbage disposal.
Run cold water into the sink and turn the disposal on to verify that this simple fix worked.
Tripped Breaker or GFCI Switch
Cause
If the garbage disposal blades don't rotate, but the motor makes a humming sound, it could be the GFCI outlet or circuit breaker has tripped. Generally, a tripped circuit breaker is due to an electrical problem, like a short-circuiting connection. GFCI outlets may trip if the garbage disposal is overheating, so it's a good idea to check whether a physical obstruction or a clog could have caused the disposal to overheat.
How to Repair
If the wiring and the disposal look fine, simply reset the GFCI switch with the reset button or reset the breaker to restore power to the garbage disposal.
Run cold water into the sink and turn the disposal on to check whether the unit is still humming or if the problem has been resolved.
If the garbage disposal is still humming, then the tripped breaker or GFCI switch is just a symptom of a larger problem you must investigate.
Overheating Unit
Cause
The motor overheating is another potential issue causing the garbage disposal to make a humming sound. This can happen if the motor is faulty, the blades are too dull to grind the food items properly, or if you are putting items into the disposal that the unit is not designed to handle. The disposal may also overheat if you have been using it for an extended period without taking a break.
How to Repair
Figure out why the disposal is overheating.
Start by turning the disposal off and allowing it to cool down.
After about 20 minutes, turn the disposal back on and test to see if it will start humming or overheating again.
If the disposal overheats when you put acceptable items into it, the blades may be too dull, causing the motor to work harder to fulfill the same function.
Try sharpening the blades by putting ice cubes and salt into the disposal. These coarse materials help refine the blades' edges, though the result may not be enough to resolve the overheating problem because blades wear out over time.
If the disposal is overheating because of a faulty motor, hire a professional plumber to repair or replace the garbage disposal. Consider the age of the unit and whether there have been any previous problems to decide on the best course of action.
Faulty Motor
Cause
Garbage disposals tend to last about 10 to 15 years, so if your unit is approaching the end of its life, a faulty motor is a sign it's time to replace the disposal. If you have checked the disposal with a flashlight to ensure there isn't a clog or an obstruction, the humming problem can be a defective motor. A faulty motor may result from a problem with the wiring, which could trip the GFCI switch or the breaker switch.
How to Repair
Changing a motor requires a technician with expertise.
Hiring an expert can cost the same, if not more, than buying a new garbage disposal.
Contact a professional plumber to get a quote so that you can make the right decision.
Garbage Disposal Safety Tips
Never put your hand or fingers into the garbage disposal.
Always ensure the unit's power is off before clearing a clog or removing a physical obstruction.
Never clean or remove a clog in a garbage disposal with a chemical cleaner. These cleaners are hazardous to your plumbing system and can spray out, harming people near the disposal.
Caring for Your Garbage Disposal
One of the best ways to prevent the garbage disposal from humming is to ensure that you maintain it properly. Never put the following items in a garbage disposal: hot grease, oil, coffee grounds, seeds, stringy fruit, fibrous vegetables, egg shells, and hard shells.
Always run cold water when you are using the disposal. This helps to solidify fatty foods, making it easier for the blades to cut through the food scraps instead of getting clogged with partially melted grease and fats.
When to Call a Professional
If you're not sure how to fix your garbage disposal or if it isn't operating the way it should, it's time to call a plumber. A simple clog or jam may be fixed without help, but something more complex or related to the motor definitely warrants a professional.
Frequently Asked Questions
Why is my garbage disposal on but not spinning?
If your garbage disposal is receiving power but not operating correctly, this is a function issue and can be caused by a jam in the motor.
How do you un-jam a garbage disposal?
A specialty wrench or an Allen wrench can be used to un-jam a garbage disposal by turning the bottom of the unit. Similarly, a long wooden utensil such as a spoon, can also be used to reach through the drain opening and dislodge whatever is causing the clog.
Where is the reset button on a garbage disposal?
Most modern garbage disposal units will have a reset button on the bottom side or near the brand logo. For older models, it may be located on the bottom of the unit.
How much does it cost to fix a jammed garbage disposal?
While repair depends on the damage, a simple jammed garbage disposal repair can cost anywhere from $75 to $100. But for something that is used everyday, the cost is worth it.
Read the original article on The Spruce.
