Eppendorf Varispenser 4962 - Manual (Page 42)

15. Troubleshooting Table
Error Cause Solution
Piston move-
ment is dif-
ficult. – Cap pushed onto dis-
charge tube.
– Formation of crystals.
– Damaged piston seal.
– Remove stopper cap.
– Immediately stop dispensing and follow
cleaning procedure (chapter 11)
Replace piston or send the dispenser
for repair if necessary. (chapter 16)
No reagent is
aspirated. – Adjusted to minimum
volume setting.
– Filling valve clogged or
sticking.
– Use volume setting knob to set higher
volume.
– Follow cleaning procedure (chapter 11).
Push filling tube all the way up onto the
filling valve. Shorten extend or replace
filling tube when necessary.
Air bubbles in
aspirated
liquid. – Instrument not properly
primed.
– Filling valve not attached
correctly or damaged.
– Reagent aspirated too
quickly.
– Filling tube loose or
damaged.
– End of filling tube is
above liquid level.
– Accomplish priming (chapter 8)
– Follow cleaning procedure (chapter 11).
Push filling tube all the way up onto the
filling valve. Shorten extend or replace
filling tube when necessary.
– Raise piston slow when aspirating
– Follow cleaning procedure (chapter 11).
Remove filling tube. Tighten valve clock-
wise or replace
– Extend filling tube so the end is below
the liquid level.
– Fill empty bottle.
Dispensed
volume too
low. – Filling valve loose or
damaged.
– Filling tube not attached
correctly or damaged.
– Follow intensiv cleaning procedure
(chapter 11.3). Remove filling tube.
Tighten valve clockwise or replace.
– Follow cleaning procedure (chapter 11).
Push filling tube all the way up onto the
filling valve. Shorten extend or replace
filling tube when necessary.
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