We think that we know what a load of laundry is supposed to look like as it runs, but the change to high-efficiency washing machines means that things look a little different. Some people even add extra water from outside the machine until it looks saturated. Don’t do that.

Our laundry-testing colleagues down the hall at Consumer Reports get very agitated when they hear about people doing this, because adding more water to the machine can actually make your clothes dingier, and interferes with the way machines are supposed to work.

“Cleaning may worsen because the clothes aren’t rubbing against each other in all that water,” Emilio Gonzalez, the engineer in charge of laundry appliance tests at Consumer Reports, explained. “It’s not what the machine’s design intended.”

As long as your clothes come out clean, that means that the machine is working as the manufacturer intended. While an older agitator top-loading machine might use up to 40 gallons of water to wash a load, a newer machine that Consumer Reports checked used only 19 gallons.

A high-efficiency front-loading machine that they tested used only 7 gallons, and a high-efficiency top-loader used only 13 gallons.

If your laundry really does seem too dry while it runs, you can adjust the cycle instead of pouring in extra water: Look for settings like a bulky items setting or a heavy duty cycle to get around the machine’s load-sensing technology.

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