Miele PWM 511 Operating And Installation Instructions page 12

Warning and Safety instructions
12
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Do not store chemicals (liquid detergents, additives) on the
machine lid. They may cause discolouration or lacquer damage.
Accidently spilled chemicals should be removed from the surface
immediately with a wet cloth.
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Only use dyes, dye removers, and descaling agents suitable for
use in a washing machine. The manufacturer's instructions on the
packaging must be observed.
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Dye removers contain sulphur compounds which can cause
damage such as corrosion. Dye removers must not be used in the
washing machine.
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Avoid contact of stainless steel surfaces with cleaning and
disinfecting agents containing liquid chlorine or sodium hypochlorite.
These agents can cause corrosion on stainless steel. Aggressive
chlorine bleach vapour can also cause corrosion. Do not store open
containers of these agents near the appliance.
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Do not use a pressure washer or hose to clean the washing
machine.