Washer-dryers: How we test
Which? tests how well each washer-dryer washes a range of nasty substances, then sets out to see how well they dry.
A sensitive subject
We get through many hundreds of loads in our laundry tests
Detergent can be irritating to those with sensitive skin.
To measure how well washer-dryers remove it during the rinsing cycle, we take freshly rinsed washing from the machine, just before the spin cycle, and spin it in a super-fast spin dryer.
This dryer spins at 2800rpm, roughly twice as fast as a typical washing machine.
After the spin, we collect water from the clothes and measure how alkaline it is compared with the alkalinity of tap water.
Detergent is very alkaline, so the greater the increase, the poorer the machine is at rinsing.
Speed cycle
Buttons and dials should be large and easy to grip
We fill the machine to capacity then time how long it takes to finish a washing or drying cycle.
We calculate the time per kilogram so that we can compare washer-dryers with different capacities.
Cleaning power
To check how well a machine removes stains, we place a cloth with chocolate, oil, blood and red wine marks in the drum along with sheets and other items of clothing.
After the wash we measure how much light is reflected off the cloth using a machine called a spectrophotometer which measures the intensity of reflected light.
The more light reflected, the better the machine is at removing stains.
Ease of Use
Big and bright lights with clear labels are best
Loading and removing washing
We look for a big drum and a large door with wide porthole that opens to 180 degrees and can be loaded with ease from a standing or sitting position.
Buttons and dials
We look for clearly marked, well spaced protruding buttons and dials, with descriptions that are self explanatory and easy to read. They should also be easy to grip and turn or activate.
Different sizes, textures and shapes, as well as noises that indicate a button has been successfully selected are helpful to people with visual impairments.
Indicator lights
Dispensers should be easy to use and replace
We prefer large and bright lights, accompanied by a clearly marked and self explanatory label, which are visible from standing and sitting positions.
Detergent dispenser
This should be easy to open and close, with no sharp edges. It should require little force and dexterity to remove and replace the detergent dispenser for cleaning.
We look for lidless compartments that are easy to access and shaped or textured to help distinguish them easily.