Garbage Disposal Not Working? Troubleshooting Guide

Your garbage disposal just stopped working. Maybe it is making a humming noise, maybe it will not turn on at all, or maybe it is leaking under the sink. Before you call a plumber or rush out to buy a new one, try these troubleshooting steps. Most garbage disposal problems can be fixed in 10 minutes with tools you already have.

Safety first: Never put your hand inside a garbage disposal, even when it is turned off. Always unplug the unit or turn off the circuit breaker before working on it.

Problem 1: Disposal Will Not Turn On (No Sound)

If you flip the switch and nothing happens — no sound, no humming, nothing — the issue is electrical, not mechanical.

Step 1: Press the reset button. Look at the bottom of the disposal unit under the sink. There is a small red or black button. If it has popped out, press it firmly until it clicks. The disposal overheated and tripped its internal breaker. Try turning it on again.

Step 2: Check the circuit breaker. Go to your electrical panel and look for the breaker labeled "disposal" or "kitchen." If it has tripped, flip it back on. If it trips again immediately, there is an electrical problem that needs professional attention.

Step 3: Check the switch and wiring. If the reset button and breaker are fine, the wall switch itself may be faulty. Test the outlet by plugging in another appliance. If the outlet works, the disposal motor may have burned out and the unit needs replacement.

Problem 2: Disposal Hums But Does Not Spin

A humming disposal means the motor is getting power but the grinding plate is jammed. Something is preventing it from rotating. This is the most common garbage disposal problem and the easiest to fix.

Step 1: Turn off the disposal immediately. Letting a jammed disposal hum for more than a few seconds can burn out the motor. Flip the switch off and unplug the unit (or cut the breaker).

Step 2: Use the Allen wrench. Most disposals come with a hex wrench, and there is a hex socket on the bottom center of the unit. Insert a 1/4-inch Allen wrench into this socket and turn it back and forth. This manually rotates the grinding plate from below, freeing whatever is jammed.

Step 3: If you do not have an Allen wrench, insert a wooden broom handle or thick wooden spoon into the disposal from above. Push it against the impeller blades and try to rotate them. Never use metal tools from above as they can damage the grinding components.

Step 4: Remove the obstruction. Use tongs or pliers (never your hand) to reach in and pull out whatever was causing the jam. Common culprits include bones, fruit pits, bottle caps, broken glass, and pieces of silverware that fell in unnoticed.

Step 5: Press the reset button (it likely popped during the jam), plug the unit back in, run cold water, and test.

Problem 3: Disposal Is Leaking

Water under the sink could be coming from several connection points. The fix depends on where the leak originates.

• Leak from the top (sink flange) — The mounting ring that connects the disposal to the sink has loosened or the plumber's putty has failed. Tighten the mounting bolts or remove the disposal, scrape off the old putty, apply fresh plumber's putty, and remount.
• Leak from the side (dishwasher connection) — Tighten the hose clamp on the dishwasher inlet. If the hose is cracked, replace it.
• Leak from the side (discharge pipe) — Tighten the bolts on the discharge pipe flange. If the gasket inside is worn, replace it (a $2 rubber gasket).
• Leak from the bottom — This usually means the internal seals have failed. A bottom leak on an older disposal typically means it is time for a replacement rather than a repair.

Problem 4: Disposal Drains Slowly

If water backs up in the sink when the disposal is running, the drain line is partially clogged.

1. Turn off the disposal and let the water drain (or scoop it out).
2. Disconnect the discharge pipe from the disposal (place a bucket underneath).
3. Check the pipe for clogs. A buildup of grease and food debris is the usual cause.
4. Clean the pipe and the P-trap below it.
5. Reconnect and run water to test.

To prevent slow draining, always run cold water for 15 to 20 seconds after turning off the disposal. This flushes debris through the drain line.

What Not to Put in a Garbage Disposal

Prevention is the best fix. Avoid putting these items down your disposal:

• Grease and cooking oil — They solidify in the drain and cause clogs.
• Fibrous vegetables — Celery, artichokes, asparagus, and corn husks wrap around the grinding components.
• Pasta and rice — They expand with water and can clog the drain.
• Bones larger than chicken wings — Large bones jam the disposal and dull the grinding components.
• Coffee grounds — They accumulate in the drain like sediment.
• Eggshells — The membrane can wrap around the grinding mechanism.
• Non-food items — Twist ties, rubber bands, plastic wrap, and labels from produce.

How to Keep Your Disposal Running Well

• Always run cold water when using the disposal (cold water keeps grease solid so it gets chopped up rather than coating the pipes).
• Feed food in gradually rather than stuffing large amounts at once.
• Run the disposal regularly, even if you do not have food to grind. This prevents rust and corrosion.
• Clean the disposal monthly by grinding ice cubes and a handful of kosher salt, then flushing with cold water. This scours buildup off the grinding components.
• Freshen it by grinding citrus peels (lemon, lime, or orange) once a week.

When to Replace vs. Repair

Garbage disposals typically last 8 to 12 years. Consider replacement if:

• The unit is leaking from the bottom (internal seal failure).
• It jams frequently despite proper use.
• It no longer grinds food effectively.
• The motor has burned out (no sound, reset does not help, power is confirmed).

A new garbage disposal costs $80 to $200 for the unit plus $150 to $250 for professional installation.

When to Call a Professional

Call a professional if the disposal needs replacement, if the leak is from the bottom of the unit, if you suspect an electrical problem, or if the drain clog is beyond the P-trap. GoldKey Repairs installs and repairs garbage disposals across Los Angeles. $150 for the first hour, $85 for each additional hour, plus parts. Call (323) 630-9115.