BRAND Dispensette S Instrucciones De Manejo página 70

10 Troubleshooting
10 Troubleshooting
Problem
Liquid is above the piston Piston leaky
Piston sluggish
Filling not possible
Dispensing not possible
Discharge tube (with or
without recirculation
valve) cannot be mounted
sufficiently
Air bubbles in the instru-
ment
Dispensed volume too
low
Leaking liquid at the re-
taining ring
70
Operating manual
Possible cause
Crystal deposits, contami-
nation
Volume setting screw at
the lower stop
Filling valve stuck
Discharge valve stuck
Discharge valve is not
screwed in deeply enough
Reagent with high vapor
pressure has been drawn
in too quickly
Screw connections loose
The instrument has not
been primed
Filling tube is loose or
damaged
Valves not firmly con-
nected or damaged
Recirculation tube not
connected
Filling tube is loose or
damaged
Filling valve contaminated,
loose or damaged
Dispensing cartridge loose
or piston seal damaged
Corrective action
Perform standard cleaning (Standard clean-
ing, p. 65), replace dispensing cartridge (Re-
placing the dispensing cartridge, p. 68).
Stop dispensing immediately. Perform stan-
dard cleaning (Standard cleaning, p. 65).
Set the desired volume (Dispensing, p. 55).
Clean the filling valve. If the valve ball is stuck,
use a 200 µl plastic tip to dislodge it (Dislodg-
ing a stick valve ball, p. 68). If necessary, re-
place the filling valve.
Unscrew the discharge valve from the valve
block and
clean it. If the valve ball is stuck, use a 200 µl
plastic tip to dislodge it. If necessary, replace
the filling valve (Replacing the discharge
valve, p. 67).
Tighten the discharge valve with the assembly
tool until it meets the stop so that the threads
are no longer visible.
Slowly draw in reagent.
Tighten the valves firmly with the assembly
tool
Prime the instrument (Priming, p. 53).
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.
Perform cleaning (Cleaning, p. 65). Tighten the
valves firmly with the assembly tool.
Install the recirculation tube (First
Steps, p. 50).
Perform cleaning (Cleaning, p. 65). Push the
filling tube on firmly. If necessary cut off ap-
prox. 1 cm of tube at the upper end and re-
connect it or replace filling tube.
Perform cleaning (Cleaning, p. 65). Tighten the
valves using the assembly tool. If necessary,
replace filling valves.
Tighten the retaining ring. If necessary, re-
place the dispensing cartridge
997491