Troubleshooting - BRAND Dispensette TA Operating Manual

Problem
Liquid is above the
piston
Piston difficult
to move
Filling
not possible
Dispensing
not possible
Air bubbles in
the instrument
Dispensed volume
is too low
Liquid leaking at the
safety ring
Leaking liquid
between instrument
and bottle
Possible cause
Piston is leaking.
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, con-
taminated, or damaged
Dispensing cartridge is loose,
or the piston seal is damaged
Recirculation tube not con-
nected
Volatile reagent dispensed
without sealing ring

Troubleshooting

Corrective action
Perform a standard cleaning, replace the piston/
cylinder assembly (see page 39-41).
Stop dispensing immediately. Follow all cleaning
instructions (page 39-41).
Set to required volume (see page 33).
Clean the filling valve.If the valve is stuck use a
200 µl pipette tip to loosen it (see page 40). If
necessary, replace the filling valve and sealing
washer.
Clean discharge valve. If necessary replace dis-
charge tube (see page 40).
Draw in reagent slowly.
Confirm that the 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 32).
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.
Follow cleaning procedure (see page 39, 42).
Tighten the valves using the mounting tool. If nec-
essary, replace the valves and sealing washers.
Connect recirculation tube (see page 31, Fig. 5).
Push the discharge tube on firmly and finger
thighten locking nuts.
Cleaning procedure (see page 39-40). 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 40).
Cleaning procedure (see page 39-40). Tighten
the valves using the mounting tool. If necessary,
replace filling valves and sealing washers.
Tighten the safety ring, and if necessary replace
the dispensing cartridge
Connect recirculation tube (see page 31, Fig. 5).
Mount sealing ring.
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