Corrective Action; Troubleshooting - BRAND Dispensette HF Instrucciones De Manejo

Troubleshooting

Problem
Piston is difficult to move
Filling not possible
Instrument does not
dispense liquid
Air bubbles in the instrument
Dispensed volume is too low
Possible cause
- Formation of crystals, dirty
- Volume adjusted to minimum setting
- Sticking filling valve
- Sticking discharge valve
- Reagent with high vapor pressure has been
drawn in too quickly
- Seal not inserted, knurled locking nuts not firmly
connected
- Air not expelled from the instrument
- Filling tube not firmly connected or damaged
- Valves dirty, not firmly installed or damaged
- Backflow tube not connected
- Discharge tube not firmly connected or damaged
- Filling tube not firmly connected or damaged
- Valves not firmly connected or damaged
- 26 -

Corrective action

- Stop dispensing immediately. Loose piston by circular motion,
but do not disassemble. Follow all cleaning instructions
( page 17).
- Set to required volume ( page 12).
- Clean filling valve ( page 19). If necessary replace the valve
with sealing washer.
- Clean discharge valve. If valve ball is stuck use yellow plastic
pipette tip (100 µl) to loosen it. If necessary replace discharge
valve.
- Slowly draw in reagent.
- Double check that seal (K) is in place, and that the knurled
locking nuts at the discharge tube and the SafetyPrime
are firmly seated and finger tight.
- Remove air ( page 11).
- 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 17). Tighten the valves using
the mounting tool. If necessary, replace the valves and sealing
washers.
- Connect backflow tube ( page 10, N).
- Push the original manufacturer's discharge tube on firmly.
Replace a deformed or damaged discharge tube.
- Cleaning procedure ( page 17. Push the filling tube on firmly.
If this does not suffice, cut off approx. 1 cm of the tube at the
upper end and re-connect it or replace filling tube
( page 31).
- Cleaning procedure ( page 17). Tighten the valves using
the mounting tool. If necessary, replace valves and sealing
washers.
valve
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