Pentair Jung Pumpen WCFIX 260 Instructions De Service page 12

ENGLISH
Therefore the cap of the tank ventilation must be removed.
Push the unwrapped activated carbon filter into the cylindric
opening.
The filter has a little interfering for a save seat. The edges of
the filter will sheare off slightly. After that, re-fit the cover. The
filter should be changed after malfunctions with overflooding
of water through the ventilation valve, in case of bad smells, it
should be changed once a year.
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