Miele S500 Operating Instructions Manual page 31

Change the dustbag when the colored
marker in the dustbag change indicator
fills the display.
The dustbags are disposable and
intended to be used only once. Do
not attempt to reuse.
The dustbag change indicator is
designed to show when the bag is full,
and works by measuring the air
permeability of the dustbag. Normal
household dust is a mixture of dust,
hair, carpet fibers, threads, sand, etc.
However, if fine dust, such as drill dust,
sand, plaster or flour is vacuumed, the
pores of the dustbag become blocked.
The marker will indicate that the bag is
"full" even when it is not. In this
instance, the dustbag must be
changed as suction power is reduced
when the pores of the dustbag are
blocked.
If a large quantity of hair, wool or carpet
fibers is vacuumed, the dustbag
change indicator may not register "full"
even though the bag is full. This is
because the air permeability of the
dustbag may still be high enough not to
activate the marker to show maximum.
The dustbag should be changed.
^ Attach the floor brush to the vacuum
cleaner. Perform this test with the
floor brush only, since other
attachments can affect the function of
the dustbag change indicator.
^ Turn the vacuum cleaner on and
select the highest power setting.
^ Lift the floor brush a little off the floor.
If the marker completely fills the
indicator window, the dustbag needs
to be changed.
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