Carpet washers

We use each carpet washer according to the manufacturer's instructions. All models are tested on the same cream carpet, each having their own sample.

Carpet cleaning

We soil the carpet samples with a mixture of clay, sand and canola oil spray, then leave them to set. The purpose is to mimic the dirt and sweat build-up typical of many months of regular use.

After cleaning, we use a spectrophotometer to compare how close each of the samples are to the carpet’s original colour.

Stain removal

Most carpet washers don't do a good job of removing stains, so this makes up only a small part of the performance score.

We soil the carpet samples with wine, gravy and coffee, and let the stains set. For each machine, we repeat cleaning cycles until there’s no visible difference between runs. We then visually assess the results, lining up the carpet samples from best to worse.

Residual dampness

We inspect each carpet sample, including undersides, for any residual dampness at 2, 4, 6 and 24 hours after use of each carpet washer.

For each carpet washer, we assess how easy it is to:

• move the cleaning head across the carpet
• fill and empty the tanks
• understand and use the controls.

We also record how much noise each carpet washer produces, measured at the user’s position.