Get the Most Out of Your Garbage Disposal with These Tips

A garbage disposal is one of the most-used appliances in a typical kitchen and one of the most commonly abused. A few simple habits will keep a quality disposal running for 10 to 12 years; a few common mistakes will cut that to a fraction. For southern New Hampshire homes, here are the rules our plumbers wish every kitchen knew.

At A.J. LeBlanc Heating, our licensed plumbers install, service, and replace garbage disposals across NH.

What you should never put down the disposal

Some foods cause immediate problems. Others cause slow problems that show up months later as a clog or motor failure:

• Grease and oil: liquid at warm temperatures, solid in the drain. Coats the inside of the pipe and eventually traps every other food particle that passes through.
• Coffee grounds: pack into a dense paste that traps everything downstream.
• Fibrous vegetables: celery, corn husks, artichoke leaves, onion skins, asparagus ends. Long fibers wrap around the impellers and choke the motor.
• Starchy foods in large quantities: pasta, rice, potato peels. Expand in water and form a paste that clogs the drain trap.
• Bones, fruit pits, shells: hard items that the disposal cannot effectively grind and that damage the impellers and grind ring.
• Eggshells: contrary to old advice, eggshell membranes wrap around impellers and the shell itself does not sharpen anything.
• Bread: expands like a sponge when wet and packs the chamber.
• Anything non-food: twist ties, utensils, plastic bag clips. Even small items can jam or damage the disposal.

What is safe in the disposal

• Small amounts of soft food scraps (cooked vegetables, salad scraps without fibrous stems)
• Small amounts of fruit (no pits or seeds bigger than a blueberry)
• Ice cubes occasionally (some plumbers suggest these help dislodge buildup)
• Citrus rinds in small pieces (refreshes the smell but do not load the disposal with them)

The disposal is designed to handle small amounts of incidental food waste rinsed off plates. It is not a trash can replacement.

How to use the disposal correctly

1. Run cold water for a few seconds before turning the disposal on.
2. Turn on the disposal, then feed food slowly. Cold water keeps grease solid so it grinds and flushes rather than coating pipes.
3. Keep running cold water for 15 seconds after the grinding sound stops, to flush the ground material through the drain.
4. Turn off the disposal, then turn off the water.

Hot water with grease is the worst combination: the grease liquefies, runs into the drain, then solidifies later. Always use cold water with the disposal.

Routine maintenance

• Monthly: drop a tray of ice cubes in and run the disposal with cold water. The ice helps scour buildup off the impellers.
• Monthly: grind a few citrus peel slices to refresh the smell.
• Quarterly: mix baking soda and vinegar in the disposal, let it foam for a few minutes, then flush with cold water. Cleans biofilm in the grind chamber.
• Avoid commercial drain cleaners. They can corrode the disposal's internal components and the rubber baffle.

Common problems and what to do

The disposal hums but does not turn

Something is jammed between the impellers. Turn off the power at the breaker. Use the hex wrench (usually clipped to the bottom of the disposal) in the hex socket on the underside of the unit. Turn back and forth to free the impellers. Restore power, press the red reset button on the bottom of the unit, and test.

The disposal will not start at all

Check that the unit is plugged in. Press the red reset button on the bottom of the unit. Check the circuit breaker. If still nothing, the motor or switch may have failed.

The disposal leaks

Leaks usually come from one of three places: the sink flange (top), the dishwasher hose connection (side), or the drain elbow (bottom and back). Leaks from the bottom of the housing usually mean the disposal is at end of life and needs replacement.

The drain is slow even after grinding stops

The drain trap or downstream pipe is partially clogged. Sometimes a P-trap removal and clean-out solves it. If not, a plumber's snake or professional drain cleaning is the next step.

When to replace vs. repair

Replacement is usually the better value when:

• The disposal is past 10 years old
• The housing is cracked or leaking from the body of the unit
• The motor hums but will not run even after clearing jams
• Grinding has gotten noticeably louder, less effective, or slower

Repair makes sense for stuck impellers, simple electrical issues, or replacing the sink flange and gaskets.

Schedule disposal service or installation

If your disposal is leaking, clogged, or past its lifespan, contact A.J. LeBlanc Heating. Our licensed plumbers install and service garbage disposals across southern NH. Serving New Hampshire families since 1928.

Frequently Asked Questions

How long does a garbage disposal last?

A quality unit (InSinkErator, Waste King, Moen) properly used lasts 10 to 12 years. Heavily used or abused units fail in 3 to 5 years.

Should I use hot or cold water with my disposal?

Always cold. Cold water keeps grease solid so it grinds and flushes. Hot water melts grease, which then solidifies in the drain downstream.

Why is my disposal humming but not working?

Something is jammed between the impellers. Turn off the power, use the hex wrench in the bottom socket to free the impellers, press the reset button on the bottom of the unit, and test.

Can I put eggshells in the disposal?

Not regularly. Despite old advice that eggshells sharpen the blades (disposals do not have blades, just impellers), the eggshell membrane wraps around the impellers and the shells themselves form a paste that builds up in the drain.

Why does my disposal smell bad?

Biofilm buildup in the grind chamber and on the rubber baffle. Clean monthly with ice and citrus peel; quarterly with baking soda and vinegar. Avoid harsh drain cleaners.