Agilent Technologies 6890 Series Service Manual page 549

840 Shutdowns
Shutdown 4—Front inlet flow shutdown
The column is plugged or not installed correctly.
Check the column and the column installation.
The inlet's pressure sensor is not operating correctly.
If you are using a split/splitless inlet:
The split ratio is too low. Increase the amount of split flow.
The inlet's proportional control valve is stuck open or closed because of
contamination or another fault.
If you are using a purged packed or cool on-column inlet:
The inlet's control valve is stuck closed because of contamination or
another fault.
Shutdown 4—Front inlet flow shutdown
This message indicates the front inlet failed to reach its flow setpoint in the
allotted time or cannot maintain its flow setpoint. When you are operating in
flow-control mode, the inlet has 2 minutes to reach the setpoint before
shutdown. The instrument will be not ready until the problem is corrected
and the inlet reaches the flow setpoint.
See Shutdown 3—Front inlet pressure shutdown for a list of potential causes
and solutions.
Shutdown 5—Back inlet pressure shutdown
See Shutdown 3—Front inlet pressure shutdown for a list of potential causes
and solutions.
Shutdown 6—Back inlet flow shutdown
See Shutdown 4—Front inlet flow shutdown for a list of potential causes and
solutions.
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Error Codes and Internal Diagnostics
Agilent 6890 Gas Chromatograph Service Manual
Jun 2001