Troubleshooting - BRAND Dispensette III Operating Manual

Problem
Piston difficult
to move
Filling
not possible
Dispensing
not possible
Air bubbles in
the instrument
Dispensed volume
is too low
Leaking liquid
between instrument
and bottle
Possible cause
Formation of crystals, dirty
Volume adjusted to
minimum setting
Filling valve stuck
Discharge valve stuck
Reagent with high vapor
pressure has been drawn
in too quickly
Seal not inserted, knurled
locking nuts not firmly
connected
The instrument has not
been primed
Filling tube is loose or
damaged
Valves not firmly connected
or damaged
Recirculation tube not
connected
Discharge tube is loose
Filling tube is loose
or damaged
Filling valve is loose
or damaged
Recirculation tube not
connected
Volatile reagent dispensed
without sealing ring for valve
block

Troubleshooting

Corrective action
Stop dispensing immediately. Loosen piston with
circular motion, but do not disassemble. Follow all
cleaning instructions (page 48-50).
Set to required volume
(see page 41).
Clean the filling valve.If the valve is stuck use
a 200 µl pipette tip to loosen it (see page 50).
If necessary replace the filling valve with sealing
washer.
Clean discharge valve. If necessary replace
discharge tube. (see page 50).
Slowly draw in reagent.
Double check that seal is in place, and that the
knurled locking nuts at the discharge tube and
™
the SafetyPrime recirculation valve are firmly
seated and finger tight.
Prime the instrument (see page 41).
Push the filling tube on firmly. If necessary cut
off approx. 1 cm of tube at the upper end and
re-connect it or replace filling tube.
Cleaning procedure (see page 48-50). Tighten
the valves using the mounting tool. If necessary,
replace the valves and sealing washers.
Connect recirculation tube (see page 38, Fig. 3).
Push the discharge tube on firmly.
Cleaning procedure (see page 48-50). Push the
filling tube on firmly. If necessary, cut off approx.
1 cm of the tube at the upper end and re-connect
it or replace filling tube (see page 50).
Cleaning procedure (see page 48-50). Tighten
the valves using the mounting tool. If necessary,
replace filling valves and sealing washers.
Connect recirculation tube (see page 38, Fig. 3).
Mount sealing ring for valve block
(see page 43).
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