A garbage disposal that won’t turn on, hums without grinding, won’t drain, or leaks can bring your kitchen routine to a halt. Most garbage disposal problems have straightforward causes, and some can be resolved without calling a plumber. Here’s a guide to the most common garbage disposal issues and what to do about each one.
At Penguin Air, Plumbing & Electrical, our licensed plumbers handle garbage disposal repairs and replacements throughout the Phoenix area
. Here’s what to check before you call.
Garbage Disposal Won’t Turn On at All
If the disposal makes no sound when you flip the switch, the problem is usually electrical:
- Press the reset button: Look for a small red or black button on the bottom of the disposal unit under the sink. If it has popped out (often triggered by an overload or jam), press it firmly until you feel it click. Then try the disposal again.
- Check the circuit breaker: Garbage disposals run on a dedicated circuit. Check your electrical panel for a tripped breaker and reset it if needed.
- Check the wall switch and outlet: Some disposals are plugged into an outlet under the sink. Verify the outlet is live (test it with another small appliance or a plug-in tester). Also check the wall switch for loose wiring if the outlet checks out.
If power is confirmed and the disposal still won’t start, the motor has likely burned out and the unit needs to be replaced.
Garbage Disposal Hums but Won’t Grind
A humming sound with no movement means the motor is getting power but the grinding plate is jammed. This is a common issue when bones, fruit pits, or hard debris get caught under the grinding plate.
To fix a jam:
- Turn the disposal OFF and disconnect power at the switch or breaker
- Insert the hex key (Allen wrench) that came with your disposal into the hex socket on the bottom center of the unit
- Work the wrench back and forth until the grinding plate moves freely
- Use tongs or pliers, never your hand, to reach in and remove any debris
- Press the reset button, restore power, and test
If you don’t have the hex key, most hardware stores carry the correct size (typically 1/4 inch). Never put your hand inside the disposal even when power is off, the grinding components are sharp.
Garbage Disposal Won’t Drain
A disposal that grinds but won’t drain has a clog in the drain line. This is often caused by starchy foods (potato peels, pasta), grease accumulation, or fibrous materials that clump together inside the drain pipe.
Do not use chemical drain cleaners in a garbage disposal, they can damage the seals and grinding components. Instead, try plunging the drain (with the disposal off) or using a drain snake. If the clog is persistent or located further down the line, our drain clearing service can clear it safely without damaging the disposal or pipes.
Garbage Disposal Is Leaking
Where the disposal is leaking tells you a lot about the cause:
- Leaking from the top (sink flange): The mounting seal between the disposal and the sink drain has failed. The disposal needs to be unmounted and the plumber’s putty or gasket replaced.
- Leaking from the side (dishwasher connection): The hose clamp on the dishwasher drain connection has loosened or the hose has cracked. Tightening or replacing the clamp/hose usually resolves this.
- Leaking from the bottom: This typically indicates an internal seal failure inside the disposal body. A bottom leak almost always means the unit needs to be replaced rather than repaired.
Garbage Disposal Makes a Grinding or Rattling Noise
A grinding or rattling sound during operation usually means a hard object, a piece of silverware, a bottle cap, a fruit pit, has fallen into the disposal and is bouncing around inside. Turn the disposal off immediately to avoid blade damage. Use tongs to retrieve the object, then test the disposal.
If no foreign object is found and the noise persists, the grinding plate or internal bearings may be worn and the unit may need replacement.
When to Replace vs. Repair
Most disposal repairs, clearing jams, resolving electrical issues, replacing the sink flange seal, are worth doing if the unit is less than 8-10 years old. If your disposal is older, leaking from the bottom, or has a burned-out motor, replacement is usually more cost-effective.
The team at Penguin Air, Plumbing & Electrical can assess whether your disposal is worth repairing or should be replaced. Call (480) 525-5400 to schedule same-day plumbing service throughout the Phoenix Valley.
Frequently Asked Questions
What should I never put in a garbage disposal?
Avoid putting grease or oil, fibrous vegetables (celery, artichokes), starchy foods (potato peels, pasta, rice), coffee grounds, eggshells, fruit pits, bones, and non-food items into your disposal. These cause jams, clogs, and premature motor wear.
Why does my garbage disposal smell bad?
Odors usually come from food residue built up on the grinding plate and inside the drain line. Run cold water and grind a tray of ice cubes to scour the grinding components, then flush with a mixture of baking soda and vinegar. Grinding a half-lemon periodically also helps neutralize odors.
How long should a garbage disposal last?
A well-maintained garbage disposal typically lasts 10-15 years. In Phoenix’s hard water environment, mineral buildup can affect seals and components slightly faster. Running cold water (not hot) while operating the disposal helps extend its life.
Can I install a garbage disposal myself?
Garbage disposal installation involves both plumbing and electrical connections. While a mechanically inclined homeowner may be able to replace a like-for-like disposal, incorrect installation can result in leaks or electrical hazards. A licensed plumber can install a new disposal quickly and correctly, with the right permits if required.
About Penguin Air, Plumbing & Electrical
Penguin Air, Plumbing & Electrical has been serving Greater Phoenix homeowners with trusted HVAC, plumbing, and electrical services since 2011. Founded by Wade Rusk and William Hallett, Penguin is locally owned and operated, available 24 hours a day, seven days a week. Our licensed, background-checked technicians serve Phoenix, Mesa, Scottsdale, Chandler, Gilbert, Tempe, Glendale, and communities throughout the Phoenix Valley.
Call Penguin Air at (480) 525-5400 to schedule service today.