Homeowner's Guide To a Malfunctioning Garbage Disposal

30 November 2021
 Categories: , Blog


A malfunctioning garbage disposal is more than an inconvenience, since it can render the sink useless until the problem is fixed. Know the causes so you can prevent problems, or at least the repair options in the event you already have a problem. 


The symptoms of a malfunctioning garbage disposal are usually obvious. You may hear horrible noises when you try to operate the disposal, or it may fail to work entirely. Sometimes the entire unit will shut down and it won't come back on. These are all signs that the disposal is jammed completely.

If a disposal isn't completely jammed, the symptoms may be more subtle. Bad odors can emanate from the drain, thanks to food particles that aren't grinding completely and washing through. If you have dual sinks, the sink without the garbage disposal may back up when running water in the disposal sink or when operating the dishwasher. Drains in both sinks may also be slow to empty.


The most common cause of disposal issues is a jam in the grinding gears. For this reasons, certain items should never be put down the garbage disposal. These include bones, non-food items, and seeds and pits. Other foods to avoid are grease, rice, pasta, and vegetable peelings. Although these foods may not cause a direct jam, they can gum up the gears so that they no longer move properly.

Sometimes these restricted items don't jam the garbage disposal but instead cause damage as they pass through. Hard items like bones can damage the grinding wheels in the disposal so that they no longer grind properly. Stress on the motor may also cause it to burn out prematurely.


You can attempt a repair yourself, but be very cautious to avoid injury. Turn off and unplug the disposal before attempting anything, and never reach into the disposal with your hand. On the bottom of the disposal is a hex nut. You can use a properly sized Allen wrench to gently wiggle this nut back and forth until it spins freely in both directions, which indicates the clog is cleared. Then, push the small button next to the nut to reset the motor. Once plugged in, the disposal should work.

If the disposal fails to operate or if you are unable to turn the nut, then you need to call a plumber. They can provide further troubleshooting to determine the cause of the disposal failure so that repairs can be made if possible. A burned out or badly damaged unit will require replacement. 

Click here for more information on contacting a plumber if your garbage disposal is failing to operate properly.