Agilent Technologies 7890A Troubleshooting Manual page 41

Low Peak Area or Height (Low Sensitivity)
Troubleshooting
• If using an inlet in split mode, check the split ratio.
• Check for leaks. (See "Checking for Leaks".)
• Check the inlet for contamination. (See "Contamination or
Carryover".)
• Check each column and verify that it was cut and
installed properly at each end.
• Verify that the column type is correct.
• Perform column maintenance: Bake out contaminants,
remove the contaminated length of column near the inlet,
and reverse and bake out the column as needed.
• Verify that the liner type is appropriate for the sample.
• Verify that the detector flow settings are correct.
• Check the supply gas purity.
• Check all trap indicators and dates.
• Verify that the method parameters are correct.
• Check sample stability.
• Check configured syringe size. Some syringe sizes are
specified at half- capacity. If the maximum syringe volume
is marked at half- height on the barrel, not at the top of
the barrel, enter twice the labeled volume when
configuring the syringe size.
If using an FID:
• Verify that the correct jet is installed.
• Check for a dirty jet.
If using a uECD:
• Replace the fused silica indented mixing liner.
• Replace and reinstall column.
• Clean the makeup gas adapter.
If using an NPD:
• Check the detector for contamination.
• Replace ceramic insulators.
• Replace the bead.
If using an FPD:
• Verify correct column installation.
Chromatographic Symptoms
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