Shutdown Symptoms; Column Shutdowns - Agilent Technologies 7890 Series Troubleshooting Manual

5

Shutdown Symptoms

Column Shutdowns

112
The GC monitors inlet and auxiliary gas streams. If a carrier gas
(which can include an auxiliary flow module or pneumatics
control module) is unable to reach its flow or pressure setpoint,
the GC assumes that a leak exists. It will warn you with a beep
after 25 seconds, and it will continue to beep in intervals. After
about 5 minutes, the GC will shut down components to create a
safe state. The GC:
• Displays Front inlet pressure shutdown.
• Turns off to avoid column damage.
• Opens oven flaps in the back of the oven halfway.
• Flashes oven temperature setpoint Off.
• Turns off all flows for the column. When viewed, their
parameters flash Off. For example, the septum purge and
column flows for a split/splitless inlet would turn off.
• Turns off all other heaters. When viewed, their temperature
parameters flash Off.
• Attempts to turn on a shut-down zone fail with an error
message.
• Turns off the TCD filament.
• Turns off the FID or FPD ignitor, and the air and fuel gas
flows.
• Turns off the NPD bead, and air and fuel gas flows.
• 7890B: Communicates with the configured MS, if present, so
the MS can react to the shutdown event.
To recover from this state.
1
Fix the cause of the shutdown. Verify the carrier gas supply.
The GC requires a delivered gas pressure of 70 kPa (10 psi)
higher than the highest pressure used in the run. See the
Agilent GC, GC/MS, and ALS Site Preparation
• Check for a broken column near the inlet.
• Check for leaks.
• Replace the inlet septum.
• Replace the inlet O-ring.
• Check the supply pressure.
2
Press the key for the device that initiated the shutdown.
Scroll to the pneumatic parameter that is flashing Off, then
press [On] or [Off].
Guide.
Agilent 7890 Series Troubleshooting