7 On Your Side, Consumer Reports: The best carpet cleaners

SAN FRANCISCO (KGO) -- Think you have dirty carpets? Consumer Reports just tested three popular carpet cleaning machines.

7 On Your Side's Michael Finney checks to see if they stand up to the tests, and earn a Consumer Reports recommendation.

Consumer Reports testers do not mess around when it comes to testing these carpet cleaning machines. Well, on second thought, that's exactly what they do.

"We use a Georgia red clay so that we can see how well these machines are removing embedded dirt from the carpet itself," said Haniya Rae, Consumer Reports Home Editor.

Testers prep the samples with a measured amount of the red clay soil and wet it with water. The samples are left to dry overnight. Then, testers clean up any loose granules with a regular vacuum.

Then, the machines are put to work!

Each carpet sample gets a total of eight passes. Two wet, followed by two dry. Then, that cycle is repeated one more time. The residual ground in dirt is measured before and after cleaning.

Testers found some big differences. "At home, you can run it over your carpets as many times as you like and it's not a big deal," Rae said. "But in terms of understanding how well a machine is working, we have very controlled tests so that we can see that a machine is doing its job."

Testers also factored in how well each machine dried the carpet samples. "We test for drying performance in carpet cleaners because you don't want a wet carpet left for potential mildew or mold growth," said Rae.

Another factor in Consumer Reports' ratings? Noise.

So, while the most expensive $470 Bissell Big Green Machine delivered excellent cleaning performance, its drying, convenience, and noise levels pushed it lower in the ratings.

In the end, the Consumer Reports recommendation went to the $260 Bissell ProHeat 2X Lift-Off Pet Carpet Cleaner.

If the idea of storing and maneuvering these machines seems overwhelming, Consumer Reports says consider hiring a professional for that deep clean, and investing in a top-scoring regular vacuum.

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