Your dishwasher has one job: to transform a kitchen full of dirty plates, bowls, cups and utensils into a rack full of sparkling clean dishes.
More than half of the 80 million households in the United States with dishwashers run the appliance at least once a week, according to the U.S. Energy Information Administration, and there’s a good chance most are making some common mistakes.
“Our bad habits can inhibit a lot of the functions [in our dishwasher],” says Michael Cornell, mentor technician for Asurion, an appliance repair company based in Nashville, Tennessee.
To get your dishes clean and prolong the life of your appliance, avoid these eight common dishwasher mistakes.
1. Failing to check the labels
Make sure an item is dishwasher-safe before turning on the machine. The heat from the drying cycle could cause wood items such as cutting boards to crack or warp, and the dishwasher will dull sharp knives and blades for food processors and other kitchen appliances. Hand-wash those items instead.
Jill Notini, vice president of communications for the Association of Home Appliance Manufacturers, advises against putting stemware or other delicate glass in the dishwasher. Not only is there a risk those glasses will break, the broken glass can wreak havoc on the appliance.
“A shard of glass could get caught ... in the pump and cause damage,” she says.
Avoid the temptation to turn on the tap and run a scrub brush across your dishes before stacking them in the dishwasher. Although 75 percent of people admit to prerinsing their dishes, according to a 2020 survey from dishwasher detergent producer Finish, the practice can backfire.
“Your soap actually needs those little food bits and sauces to bind to,” Cornell says. “Food particles almost act as … an abrasive to help the soap knock loose [foods] that are a little bit more baked on.”
Prerinsing removes the food bits, which can make detergent bind to porous surfaces of the dishes instead, and that will leave a film on your dishes.
Skipping the prerinse doesn’t just save time; rinsing the dishes before loading the dishwasher uses up to 20 gallons of water, according to Energy Star — and that’s before you even power on the machine. Even if the food is caked on, using the “rinse” feature on the dishwasher uses far less water than running the dishes under the tap to soften and remove excess food.