Retention Times Not Repeatable - Agilent Technologies 7697A Troubleshooting Manual

Retention Times Not Repeatable

Agilent 7697A Troubleshooting
• Check the GC. See the GC's troubleshooting information.
GC problems can include:
• Leaks in the inlet, including septum
• Leaks around the inlet liner, if applicable
• Gas supply pressure
• Wrong liner type used, if applicable
• First run effects (has the GC stabilized?)
• Check the HS sequence log, event log, and status displays
for messages. Especially check the sequence log for
method deviations and dynamic leak check failures.
• If using HS carrier gas control, confirm that the current
HS column configuration matches the column actually
installed in the GC.
• Check for leaks in the transfer line to the GC inlet,
including the connection to the inlet.
• Check for leaks in the other parts of the sampling system
(probe, six port valve, and lines and fittings between).
• Enable dynamic leak checking. This feature verifies that
each sample vial is leak- free.
•
If not enabled, check the sample vial for cracks or
other leaks. See the
• If using dynamic leak checking, make sure the entered
leak rate is appropriate for the sample and its
preparation technique.
Chromatographic Symptoms
Operation Guide.
2
19