Troubleshooting - BRAND seripettor FEP Operating Manual

Troubleshooting

Problem
Piston difficult to move
Liquid above piston seal
Filling not possible
Dispensing not possible
Air bubbles in the
instrument
Dispensed volume
is too low
48
Possible cause
Formation of crystals
Dispensing of incompatible
liquid
Dispensing cartridge worn
Valve not correctly mounted
Volume adjusted to minimum
setting
Sticking filling valve
Dispensing cartridge worn
Sticking discharge valve
Reagent with high vapor pres-
sure has been drawn in too
quickly
The instrument has not
been primed
Dispensing cartridge worn
Filling tube not firmly con-
nected or damaged
Valves not firmly connected,
contaminated or damaged
Discharge tube not firmly
connected or damaged
Filling tube not firmly
connected or damaged
Filling valve not firmly
connected or damaged
Frequent dispensing > 40 ºC
Corrective action
Replace dispensing cartridge (page 43).
Check for operating exclusions
('Dispenser selection chart', page 31).
Replace dispensing cartridge (page 43).
Mount valve correctly (pages 41, 42).
Set to required volume (page 36).
Clean filling valve (pages 41, 42). If nec-
essary, replace the valve and sealing ring
(observe operating exclusions, page 30).
Replace dispensing cartridge (page 43).
Clean discharge valve. If necessary replace
discharge valve.
Slowly draw in reagent.
Prime the instrument (page 35).
Replace dispensing cartridge (page 43).
Cleaning procedure (page 40). 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 (page 40). Tighten fill-
ing valve and discharge tube. If necessary,
replace valves and seals.
Push the discharge tube on firmly. Replace a
deformed or damaged discharge tube.
Cleaning procedure (page 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.
Cleaning procedure (page 40). Tighten filling
valve. If necessary, replace valve and sealing
ring.
Replace dispensing cartridge (page 43).