Plumbing service
Garbage disposal repair and installation
Short answer
A disposal that hums but won't spin is usually jammed. With the power off, turn the flywheel using the hex key socket on the bottom, then press the reset button. One that does nothing may have tripped its reset or breaker. A leak from the unit's body usually means replacement; leaks at the sink flange or drain connections can usually be fixed.
Updated · Editorial team; not yet technically reviewed
Garbage Disposal Repair and Installation at a glance
- Hums, won't spin
- Jammed; free it with the hex key (power off), then reset.
- Silent
- Reset button, switch, breaker or outlet.
- Leaks
- Sink flange, dishwasher hose, drain connection, or the housing (replace).
- Slow drain
- Food buildup in the trap or kitchen line; see drain cleaning.
Clearing a jam safely
Cut the power
Turn off the wall switch and unplug the unit or switch off its breaker.
Turn the flywheel
Insert the hex key (usually 1/4 inch) into the socket on the bottom center and work it back and forth until it turns freely.
Remove debris
Use tongs or pliers from above, never your hand.
Reset and test
Press the red reset button on the bottom, restore power, and run cold water before switching it on.
Finding a leak
| Where | Cause | Fix |
|---|---|---|
| Top, at the sink | Plumber's putty or mounting failed | Reseal the sink flange |
| Side, dishwasher hose | Loose clamp or cracked hose | Tighten or replace |
| Side, drain outlet | Worn gasket or loose bolts | Replace the gasket |
| Bottom, housing | Internal seal failure or corrosion | Replace the unit |
What not to put down a disposal
- Grease, oil and fat, which harden in the line
- Fibrous scraps (celery, corn husks, onion skins)
- Starchy foods like pasta, rice and potato peels, which swell and paste up
- Coffee grounds and eggshells in quantity, which build up as sediment
- Bones, fruit pits and non-food items
Replacing a disposal
Many new disposals mount to the same sink flange style, which makes replacement straightforward. Consider motor size for your use, a model with sound insulation, and whether your home is on septic, since some are designed for septic systems. Check whether your city restricts disposals or requires specific connections, and connect the dishwasher drain properly if you knock out the dishwasher inlet.
What affects the cost
- Motor size and features such as sound insulation or septic-rated models
- Whether the existing sink flange and mounting can be reused
- Electrical work if there's no switched outlet or hardwired connection
- Dishwasher drain connection
- Clearing a clogged trap or kitchen line found during the job
We don't publish prices; they vary by market. Get a written quote first.
Problems that lead to garbage disposal repair and installation
- Sink not drainingWhy a kitchen or bathroom sink won't drain, the order to try fixes in, how to clean a P-trap, and when the clog is past the trap.
- Garbage disposal jammedHow to free a jammed garbage disposal with the hex key, reset it, and tell a jam from a dead motor or a leak that means replacement.
Common questions
How long do garbage disposals last?
Many last around a decade with normal use. Leaks from the housing, frequent jams, or a motor that trips its reset often mean it's time to replace.
Why does my garbage disposal hum but not work?
The motor is getting power but the flywheel is jammed. Free it with the hex key from below with the power off, then press reset.
Can I use a garbage disposal with a septic system?
Often yes, but it adds solids to the tank, which may need pumping more often. Some models are designed for septic use.