Read "Electrolux, are they ok too"? Wpool duet discussed on there comparing with Elux.

Hardly any washer uses a dedicated steam generator any more - it's all done by the heating element under the drum. Depending on the manufacturer, "steam" is either a small bit of water heated to steam (just like you would steam vegetables) or the machine simply turns on the heater to boost or maintain the wash water temp.

The dryer just sprays water in the drum that turns to steam by the heat of the drying cycle. Throwing a wet wash cloth in with dry clothes has the same effect as a steam cycle. There is a fine nozzle in the back of the dryer drum that sprays water - if you want want to descale something, just wipe that nozzle or use a tooth brush. The washer is easily descaled with some citric acid.

Alex