Download 7890 Series GC Troubleshooting

3
Chromatographic Symptoms
Peaks Not Displayed/No Peaks
• If using an autosampler:
• Ensure that there is sample in the vial.
• Verify that the ALS plunger carriage is secured to the
syringe plunger.
• Check that the syringe is installed correctly and draws
sample.
• Verify that the turret/tray is loaded correctly and
injections are not from out- of- sequence vials.
• Watch to see that the sample is pulled into the syringe.
• Verify the detector in use is assigned to a signal.
• Check the column for proper installation.
• Ensure that the column is not plugged. (See “To Measure
a Column Flow”.) Perform column maintenance.
• Check for leaks. (See “Checking for Leaks”.)
• Check the flow settings, then measure the actual detector
flows. (See “To Measure a Detector Flow”.)
• Some samples change with heat or ultraviolet light. Check
sample stability.
• Check the sample level in the vial.
• If the sample is viscous, try the following:
• Increase the viscosity delay time.
• Dilute the sample in an appropriate low- viscosity
solvent.
• Turn the tower fan off.
• For 7683B ALS, use the tray quadrants to warm the
sample. For 7693A ALS, use the vial heater (accessory
G4514A Bar Code Reader/Mixer/Heater) to warm the
sample vial.
If the problem is with the detector, see Table 3.
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Agilent 7890 Series Troubleshooting