Turn on the water before you turn on the disposal
Start the cold water flowing at full pressure before you flip the disposal switch. Let the water run for a few seconds to fill the sink basin, then turn on the disposal. This matters because water helps push food down the drain and keeps the grinding chamber cool. If you run the disposal dry, the motor works harder and heat builds up inside.
Keep the water running the entire time the disposal is on. Once you finish feeding food scraps, leave the water and disposal running for another 10 to 15 seconds. This clears the last bits from the grinding chamber and prevents clogs from forming just below the sink.
Key Takeaways
- Always run cold water before, during, and for 15 seconds after using the disposal to prevent clogs and cool the motor.
- Feed small amounts of soft food scraps slowly into the running disposal, never dump a full plate at once.
- Never put bones, fruit pits, fibrous vegetables, grease, or pasta into the disposal because these jam the blades or cause drain blockages downstream.
- If the disposal stops or makes a grinding noise, turn it off when ready, wait 30 seconds, and use tongs to remove the stuck object—never put your hand down the drain.
- Run the disposal once or twice a week even with no food scraps to keep the blades and drain clear of buildup.
Feed food scraps in small amounts, not all at once
Drop a handful of soft food scraps into the drain opening while the water and disposal are running. Soft foods—vegetable peels, cooked meat scraps, leftover rice, bread crusts—break down easily. Wait for that batch to disappear completely before adding more. This takes only a few seconds per handful.
Never dump an entire plate of food into the disposal at once. The grinding chamber is small, and overloading it forces the motor to work too hard, slows the drain, and can jam the blades. Think of it as feeding a small animal: little bites, one at a time, not a whole meal dropped at once.
Foods that will jam or clog your disposal
Bones are the most common cause of disposal jams. Even small chicken bones or fish bones are too hard for the blades to grind into small enough pieces. Throw bones in the trash instead.
Fruit pits (peach, cherry, avocado) and hard seeds will not break down and will jam the blades. Fibrous vegetables like celery, corn husks, and onion skins wrap around the blades and stop them from spinning. Grease and oil cool and solidify inside the drain pipes below the sink, creating blockages that affect your whole plumbing system—pour grease into a container and throw it away.
Pasta, rice, and bread absorb water and swell inside the drain, causing clogs. Coffee grounds clump together and build up over time. When in doubt, throw it in the trash or compost instead of risking a clog.
What to do if the disposal jams or stops
If the disposal suddenly stops or makes a loud grinding noise, turn it off when ready. Do not try to restart it. Wait 30 seconds for the blades to stop completely.
Use a flashlight to look down the drain opening. If you can see the stuck object, use tongs or needle-nose pliers to pull it out. Never put your hand or fingers into the drain, even if the disposal is off—the blades are sharp and a sudden restart could cause injury.
If you cannot see the blockage or cannot reach it with tongs, the jam is likely deeper in the drain pipe. Turn off the disposal at the wall switch and leave it off. Call a plumber rather than trying to force the disposal to run, which can damage the motor or push the blockage further down the pipes.
Cleaning and maintaining your disposal
Once a week, run the disposal with cold water and no food scraps for 10 to 15 seconds. This clears any buildup inside the grinding chamber and keeps the drain flowing freely. If you notice a smell coming from the sink, the disposal itself may need cleaning.
To clean a smelly disposal, fill the sink with cold water, add a handful of ice cubes and half a cup of baking soda, then turn on the disposal. The ice helps scour the blades and chamber walls while the baking soda neutralizes odors. Run it for 10 to 15 seconds, then flush with cold water. Do not use hot water or bleach, which can damage rubber seals inside the unit.
When to turn off the disposal at the wall switch
Your disposal has a wall switch near the sink. Turn it off at the switch (not just by stopping the flow of food) when you are finished using it, after the water has run for 15 seconds. This is the normal way to stop the disposal.
Turn off the wall switch and leave it off if the disposal is jammed, if you smell burning plastic or rubber, or if water is leaking from under the sink. A burning smell means the motor is overheating or something is caught. Leaking water means a seal has failed. In both cases, stop using the disposal and call a plumber before you try again.
Frequently Asked Questions
Can I use hot water in my disposal?
No. Hot water melts grease, which then cools and hardens inside the drain pipes below the sink, causing clogs. Always use cold water. Cold water also keeps the motor cooler during operation.
What if my disposal smells like rotten food?
Food particles and bacteria can build up inside the grinding chamber. Run the disposal weekly with ice cubes and baking soda as described above. If the smell persists after cleaning, the rubber seal or gasket may be deteriorating, and a plumber should inspect it.
Is it okay to put eggshells down the disposal?
Eggshells are borderline. The membrane inside the shell can wrap around the blades, and the shell itself is harder than soft food scraps. Most plumbers recommend throwing eggshells in the trash to be safe, especially if your disposal is older or smaller.
How long should the disposal run after I stop feeding it food?
Keep the water and disposal running for 10 to 15 seconds after the last food scrap disappears. This clears the grinding chamber and prevents bits from sitting in the drain and rotting.
What does it mean if the disposal hums but does not spin?
A humming sound with no spinning means the blades are jammed. Turn off the disposal when ready and use tongs to remove the stuck object. Do not force it to run, as this can burn out the motor.