If there is one thing your plumber wants you to know about your home garbage disposal, it is this: It’s not for garbage. In fact, the correct term and use is “food waste disposal” and there is a limit on what it can handle.
Improper use and care of a garbage disposal can also lead to clogged drains and mechanical malfunctions.
Mounted to the underside of your sink, a disposal uses a spinning disc called an impeller plate to pulverize food waste into tiny bits that get washed away by water. They’ve been around grinding up food waste since they were invented in 1927.
“Everyone calls them ‘garbage disposals,’” said Steve Farren, master plumber at General Mechanix in Bangor. “But they are for food waste and if you won’t eat it, don’t put it down the disposal.”
Here are some basic dos and don’ts for keeping your disposal system and your drains running smoothly.
When in doubt, throw it out
Putting the wrong things down your disposal can leave you with problems ranging from clogged pipes to smelly drains to a damaged disposal.
The most important rule of thumb is to remember your disposal is not a trash can. It’s for food scraps only. Do not put anything into the disposal that is not biodegradable because non-food items can damage both the impeller plate and the motor.
That also means no glass, plastic, paper, combustibles or cigarette butts.
“I once pulled eight bottle caps out of a jammed disposal,” Farren said. “The girl living in the apartment looked at me like I had three heads when I told her she can’t put metal down the disposal.”
Exceptions to the rule
There are some food items that should never go down your disposal, even if they are biodegradable and/or edible. Fibrous materials like corn husks, celery stalks, onion skins and artichokes can tangle and jam the disposal. Starchy foods like potato peels can turn into a thick paste and cause the impeller plate to stick.
Foods like rice and pasta that expand when you cook them will do the same thing in your pipes, creating clogs. Your disposal will do an excellent job of pulverizing eggshells, but that’s a problem, according to Farren.
“The disposal will pulverize eggshells into such tiny pieces they won’t go anywhere,” Farren said. “They just sit at the bottom of the drain trap and accumulate there until you get a clog.”
Coffee grounds, he said, do the same thing.
So what can go down the disposal?
According to Consumer Reports, depending on the horsepower of your disposal, food scraps from peach pits to corn cobs to cooked steak are things that can be ground up by the disposal and washed down the drain. Peels from oranges, lemons or limes can also go down and have the added benefit of making your drain smell nice.
Small bones from fish can be tossed in, but avoid large bones like steak or poultry that can jam up the disposal.
“I once had someone try to jam an entire Thanksgiving turkey down a disposal,” Farren said. “It seems every Thanksgiving I’m having to pull whole turkey thighs out of drains.”
Keep it cool
You should always run water down the drain while the disposal is operating. While it may seem smart to use hot water to wash things down your disposal and drain, Farren said you should always use cold water.
“There are two reasons for this,” Farren said. “Using cold water can keep your disposal motor from overheating and using hot water allows anything oily or greasy to soften up and then accumulate when it cools.”
Cold water will solidify oils so they can be chopped up and washed away.
It’s also a good idea to toss ice cubes into your disposal once a week or so, Farrend said.
“It’s going to be really noisy,” he said. “But crushing up the ice cubes does a great job sharpening it up.”
Used properly, a disposal system can be a help in reducing the amount of food your home puts in the waste stream. But Farren said they may not be for everyone.
“If you want to go green and have the space for it, the best thing is to start a food compost bin,” he said. “Everything you put into a disposal you can put into your compost.”