Thermo Scientific Accela Open Autosampler Hardware Manual page 107

Table 29. Troubleshooting using symptoms and error messages (Sheet 5 of 5)
Symptom or error message
Excessive carryover between
samples
Thermo Scientific
Possible cause
Dirty needle, holding loop, and/or
valve injection port
Inappropriate wash solvent or
solvents
Waste tubing ID too small at
injection valve, causing waste liquid
to be pulled back, by capillary
action, into rotor groove.
Damaged or grooved valve rotor
Leaking valve needle seal
Inappropriate wash solvent
composition
Tube of holding loop at end not cut
square or nut/ferrule fixation not
correct.
DLW Actuator/Solenoid
questionable or defective
Blocked solvent frits in wash solvent
reservoir
Troubleshooting Using Observed Symptoms or Error Messages
Recommended action
Increase Pst Inj Slv1/Slv2 values in method
(cleaning time).
Use PreClnSlv1/Slv2 and PreClnSpl.
Use appropriate wash solvents.
Replace the waste tubing with larger ID tubing.
Replace valve rotor.
Change valve needle seal.
Use appropriate wash solvent. Also observe the
order of use for biological samples. First wash is
always an aqueous solution followed by organic
solvents.
Check the connections from the holding loop:
• Is the pilot distance appropriate?
• Is the tube end damaged?
• Is the tube end cut absolutely square?
• Are the right nuts and ferrules used?
Verify the functionality of the DLW Actuator.
Is solvent flowing when active? Use command
Utilities > Wash Station to test.
Clean the frits in an ultrasonic bath with an
appropriate solvent. If flow is not ensured after
cleaning, replace frits.
Replace wash solvent and clean reservoir bottle
and tubing carefully.
Accela Open Autosampler Hardware Manual
6
Troubleshooting
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