Miele DA 259-4 Operating And Installation Instruction page 20

If the cooker hood is connected for
recirculation two active charcoal filters
must be inserted in addition to the
grease filters. These filters absorb
normal kitchen odours.
They are fitted in the canopy above the
grease filters.
Active charcoal filters can be
obtained from your dealer or the
Miele Spare Parts Department.
Refer to the section "Technical data"
for type and reference number.
The filters are supplied with fitting
instructions. Ensure these are carefully
followed.
Replace the filters when they no longer
absorb kitchen odours effectively.
They should, however, be replaced at
least every 6 months.
Used charcoal filters can be disposed
of with the normal household waste.
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