Agilent Technologies 7890A Troubleshooting Manual page 35

Peak Boiling Point or Molecular Weight Discrimination Poor
For any inlet operating in split mode with any detector
For any inlet operating in splitless mode with any detector
Troubleshooting
If you have trouble with peak boiling point or molecular
weight discrimination (inlet discrimination), do the following:
• Check the inlet for contamination. Clean and change the
liner if necessary. Replace all inlet consumable parts. See
the Maintenance manual.
• Adjust the inlet temperature.
• Run standards against a known method to determine
expected performance.
• Check liner type.
• Increase the inlet temperature and verify that the
insulation cup is installed and contains insulation.
• Check column cut and installation into the inlet. See the
topic for the SS, MMI, PTV, and VI.
• Check the inlet for leaks. (See "Checking for Leaks".)
• Check liner type.
• Verify that the oven starting temperature is less than the
solvent boiling point.
• Check column cut and installation into the inlet. See the
topic for the SS, MMI, PTV, and VI.
• Check that the solvent vapor volume does not exceed the
liner capacity.
• Check for appropriate purge delay time.
Chromatographic Symptoms
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