Turn it on only after food is in the drain
A garbage disposal works by grinding food waste into small particles that wash down the drain with water. The motor and spinning blades stay off until you flip the switch. Always put food down the drain first, then turn on the disposal, then run cold water. Never reach into the drain or turn it on while your hand is anywhere near the opening.
The water does two things: it helps the blades grind the food into smaller pieces, and it carries those pieces down the drain pipe. Without water, the disposal will jam and the food will sit in the chamber. Cold water is better than hot because it keeps grease solid so the disposal can break it up instead of letting it coat the pipes downstream.
Key Takeaways
- Always run cold water before, during, and after using the disposal to flush food particles down the drain and prevent jams.
- Never put your hand or any object into the drain while the disposal is running, and never try to force stuck food down by hand.
- Avoid putting fibrous foods like celery, corn husks, and onion skins down the disposal because they wrap around the blades and cause jams.
- Grease and oil should go in the trash, not down the drain, because they cool and harden in the pipes even if the disposal grinds them first.
- If the disposal stops grinding or makes a strange noise, turn it off when ready and call a plumber rather than trying to fix it yourself.
Foods that jam or damage the disposal
Fibrous and stringy foods are the main culprit. Celery, corn husks, artichoke leaves, onion skins, and carrot peels wrap around the spinning blades and stop them from turning. Banana peels, potato skins, and asparagus do the same thing. Even small amounts can cause a jam that stops the whole unit.
Bones, pits, and shells should never go in. The blades cannot break them down, and they either jam the motor or damage the blades themselves. Pasta and rice are also risky because they absorb water and swell inside the chamber, creating a paste that clogs the drain. Grease and cooking oil should go in a container in the trash—even though the disposal can grind them, they cool and harden in the pipes downstream and cause blockages that a plumber has to clear.
What to do if it jams or stops grinding
Turn off the disposal when ready and do not try to reach in or force anything down. If the blades have stopped turning, something is stuck. Unplug the unit from the outlet under the sink, or flip the breaker switch if it is hardwired. Wait a few seconds.
Look into the drain with a flashlight. If you can see the stuck object and reach it with tongs or pliers, remove it. Do not use your fingers. If you cannot see anything or cannot reach it, or if the disposal makes a grinding or squealing noise when you turn it back on, stop and call a plumber. Trying to force it or disassemble it yourself can cause injury or damage the unit beyond repair.
How to clean and deodorize the disposal
Run cold water and the disposal for a few seconds after every use to flush out food particles. Once a week, pour half a cup of baking soda down the drain, followed by half a cup of white vinegar. The mixture will fizz—let it sit for 15 minutes, then run cold water and the disposal for 30 seconds. This breaks down buildup and removes odors without chemicals.
Never pour bleach or drain cleaner down a disposal. These chemicals can damage the rubber seals and metal parts, and they do not help clear jams. If the disposal smells bad and baking soda and vinegar do not help, the smell is usually coming from the drain pipe below, not the disposal itself, and a plumber should inspect the line.
When to call a professional
Call a plumber if the disposal makes a loud grinding or squealing noise, if it stops grinding even after you clear visible jams, if water backs up into the sink when you run it, or if it leaks from the bottom. These are signs of internal damage, a clogged drain line, or a seal failure. Trying to fix these yourself can make them worse and more expensive to repair.
Also call a plumber if the disposal will not turn on at all. It may be a tripped breaker or a blown fuse, which you can check yourself, but if resetting the breaker does not work, the motor or electrical connection has failed and needs professional service.
Maintenance to extend the life of your disposal
Run cold water for a few seconds before and after each use. This flushes the chamber and prevents food from drying and hardening inside. Once a month, run the disposal with cold water for 30 seconds while it is empty—this clears any buildup on the blades.
Keep the rubber splash guard clean by wiping it down with a damp cloth. Food can accumulate under it and cause odors or attract pests. If the guard cracks or tears, replace it—it is inexpensive and protects your sink from splashing. Avoid putting anything down the drain except food waste and water. Bones, glass, metal, and plastic will damage the blades or jam the motor.
Frequently Asked Questions
Can I put coffee grounds down the garbage disposal?
Yes, small amounts of coffee grounds are fine and will not jam the disposal. However, they can accumulate in the drain pipe over time and contribute to clogs. If you use the disposal often, put most grounds in the trash or compost and rinse only a small amount down the drain.
What should I do if the disposal is leaking from underneath?
Turn off the disposal and unplug it. Check the rubber gasket and bolts where the disposal connects to the sink drain. If bolts are loose, tighten them with a wrench. If the gasket is cracked or the leak continues after tightening, the unit needs to be replaced. Call a plumber to do this safely.
Is it safe to use a plunger on a sink with a garbage disposal?
Yes, but turn off the disposal first and make sure it is not running. Use a cup plunger (the flat-bottomed kind) on the sink drain. A plunger can help clear clogs in the drain pipe below the disposal. If plunging does not work, the clog is deeper in the line and a plumber should clear it.
Can I put eggshells down the garbage disposal?
Small amounts are usually okay, but eggshells are harder than most food waste and can dull the blades over time. The membrane inside the shell can also wrap around the blades. It is safer to put eggshells in the trash or compost.
How long should a garbage disposal last?
A well-maintained disposal typically lasts 8 to 15 years. Regular cleaning, avoiding hard and fibrous foods, and running water before and after each use extend its life. If yours is older and breaking down frequently, replacement is usually cheaper than repeated repairs.