How to Clean a Garbage Disposal and Stop the Smell (Without Putting a Hand Inside)

Step by step

1. 1

   Cut the power

   Look under the sink. If the disposal has a plug, pull it out of the outlet. If you do not see a plug, it is wired in, so turn its power off at the electrical box.

2. 2

   Take out the splash guard

   The splash guard is the rubber ring of flaps that sits in the drain opening. InSinkErator says the baffle on its models lifts out for cleaning. If yours does not come out, scrub it where it sits in the next step.

   What it looks like: any buildup on the underside of the flaps is the usual source of the smell. InSinkErator’s manual calls an odor “a sign of grease and food buildup.”

3. 3

   Scrub the splash guard with baking soda

   Wet a dish brush, sprinkle baking soda on it, and scrub the underside of every flap with warm water. Then brush the inside upper lip of the drain opening, which the manual also says to clean. The brush does the reaching, so your fingers stay above the sink.

   Rinse the guard and the brush with warm water. Moen notes that its own splash guard is dishwasher safe.

4. 4

   Put it back and turn the power on

   Press the splash guard back into the opening until it sits flat. Then plug the disposal back in, or switch its power back on.

1. 5

   Do the baking soda flush

   Put the stopper in the drain and fill the sink about halfway with warm water. Stir in 1/4 cup of baking soda. Then turn the disposal on and pull the stopper out at the same moment. That is the cleaning method in InSinkErator’s own care manual.

   What it looks like: the water rushes down through the running disposal and carries loose bits out with it.

2. 6

   Grind citrus wedges with cool water

   Cut a lemon or an orange into wedges. Turn on a steady stream of cool water, turn the disposal on, and drop the wedges in one at a time. That is how InSinkErator’s cleaning page says to do it, and the maker says citrus helps clear away odors.

3. 7

   Finish with ice and a long cold rinse

   With the cold water still running, grind a few ice cubes. Ice knocks loose bits off the grinding parts, though InSinkErator says it usually melts before it cleans the whole chamber. When the grinding stops, let the cold water run at least 15 more seconds to flush the drain line.

Habits that keep the smell away

Once it is clean, a few small habits keep it from souring again.

1. Cold water, every time. Run a strong stream of cold water while you grind and for at least 15 seconds after. The manual says not to use hot water while grinding.
2. No grease down the drain. InSinkErator says fats, oils and grease should never go in a disposal or any sink drain. Let grease cool in a can and throw it in the trash.
3. Feed it a little at a time. Coffee grounds and eggshells will not hurt it, the maker says, but add them slowly, because older pipes can clog if a lot goes down at once.
4. Keep stringy food out. The manual says very fibrous scraps like corn husks and artichokes can plug the drain.

When it will not work, and what to do instead

Sometimes the smell hangs on after a good cleaning. Here is what to check.

• The sink drains slowly or water sits in it. Moen says a clogged or slow disposal can start to smell on its own, so the clog has to go first. InSinkErator’s manual says never to put drain cleaner in it. Call a plumber if water will not go down.
• The splash guard is torn or worn out. Replacement guards are sold for many disposals. Moen, for one, sells a splash guard and stopper set for its models.
• Tiny flies hover over the sink. Garbage disposals are on the University of Kentucky’s list of places fruit flies breed. Clean the disposal as above, then see Why fruit flies keep coming back.
• You were told hot water melts the grease away. It makes sense that heat would help, since hot water does melt grease. But InSinkErator says cool water keeps fat solid as it passes through the disposal and your pipes, and grease that collects inside pipes is behind many plumbing problems.

Why it works

InSinkErator says its disposals have no blades at all. Parts called impellers push the food against a grinding ring that shreds it, a little like a cheese grater.

That grinding leaves grease and food behind on parts you never see. The maker’s manual says an odor is usually a sign of exactly that buildup, so the fix is to scrub it off, not cover it up.

Cold water matters for the same reason. Think of bacon grease in a pan: warm, it pours, and cold, it turns white and solid. Cold water keeps grease in solid bits that wash on through.