The (Dirty) Truth About the Steam Setting on Washing Machines – ConsumerReports.org

To evaluate how steam affects cleaning performance, we tested five front-loaders, one HE top-loader, and one agitator top-loader washer from five manufacturers: Electrolux, LG, Maytag, Samsung, and Whirlpool.

First, we ran our usual wash-performance tests. CR testers use a spectrocolorimeter to analyze fabric swatches stained with red wine, cocoa, and carbon (which is similar to soot), among other stains, before and after washing, using the normal wash cycle and heaviest-soil setting. The lighter the reading for the stain after laundering, the higher the model scores in cleaning. Then we repeat this test with new fabric swatches using the same wash cycle, but this time adding steam. 

“Stain removal was about the same with or without steam,” says Handel. “But the steam option did cause most of the machines to use more water, and all of them used more energy.” 

Using the steam function extended cycle times substantially for some washers, doubling it in one case. Even worse, one washer’s steam option increased water consumption by 18 gallons and energy use by nearly 600 percent, erasing years of efficiency gains. 

Jim Nanni, head of appliance testing at Consumer Reports, notes that one likely reason steam has little effect on cleaning is that the laundry is saturated with water or submerged in it, so that any effect that steam can have on cleaning is minimized or even negated. Plus, the steam probably isn’t delivered at a high enough temperature to help lift or remove stains.

“In many cases, the steam dispensed onto your load of
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