Siemens 
D12-52 Operating And Installation Instruction page 47

Descaling the
washer dryer
Attention
Descaling agents contain acids which may corrode
the components of the washer dryer and discolour
the laundry.
Provided that you use the correct amount of deter
gent, it is not necessary to descale the washer dryer.
If descaling is nevertheless required, please follow the
instructions supplied by the manufacturer of the
descaling agent.
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