Wamsler 101 90 SYSTEM E Mode D'emploi page 29

Cleaning of the soapstone: the soapstone is a natural stone, therefore minor
colour differences may occur; as it is normal, they may not serve as a basis for
quality complaints! To clean the soapstone from dirt and fat with water and soap,
as well as small scratches, use sand paper (grain size 240).
Warning: Under no circumstances you may use sponge, scouring,
aggressive or scratching cleaning agents! If the grate is blocked so that the
equipment cannot serve the intended function, the grate is to be removed for
cleaning.
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