General Points Regarding Chromatographic Effects - Thermo Scientific TriPlus RSH User Manual

6
Analytical Troubleshooting

General Points Regarding Chromatographic Effects

General Points Regarding Chromatographic Effects
Table 96. General Points Regarding GC Effects - Troubleshooting Guideline (Sheet 1 of 3)
Symptom or Error Message
Very low or no detector signal is
observed.
Syringe does not fill properly.
228 TriPlus RSH User Guide
This sections provides general troubleshooting guidelines regarding the chromatographic
effects:
Possible Cause
Clogged syringe.
Bent syringe needle or bent plunger.
No sample liquid is injected.
Sample volume too low.
Wrong setting of syringe needle
penetration in GC injector.
Air bubbles below syringe plunger. It is
possible that air bubbles remain below
the plunger after the first pull-up. If
the plunger is moved up and down
several times, these air bubbles are
worked out.
Wrong type of syringe assigned to tool
holder.
Syringe needle penetration depth in
vial incorrect.
Syringe plunger polymer tip worn out. Manually check the tightness of the polymer
Glass barrel cracked.
Recommended Action
Remove syringe and aspirate/dispense liquid
manually.
Clean syringe.
Inspect the syringe. Replace it if necessary
Note: Bottom Sensing using a long needle
(85 mm) has a high risk of needle bending.
How to remove a syringe with a bent needle
or plunger is explained in the section
Manually Removing a TriPlus RSH Tool
from the RSH Head of the TriPlus RSH
Hardware Manual.
Check, adjust, the needle penetration into
sample vial.
Increase sample volume.
Check Needle Penetration Depth settings
and compare with GC manufacturer
recommended parameters.
Increase method parameter Def Fill Strokes
Count (Fill Strokes).
Check the method parameters Def Aspirate
(Fill Speed) and Def Aspirate Delay (Pull-up
Delay).
Check the syringe parameters to ensure that
the correct syringe type is assigned to the tool
holder. Verify the scale length parameter.
Check the syringe needle penetration depth in
the sample vial.
plunger tip. When in doubt, replace the
plunger.
Check the integrity of the syringe. When in
doubt, replace the syringe.
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