8
Troubleshooting Tasks
To Measure a Split Vent or Septum Purge Flow
WA RNING
Back inlet split
vent
Front inlet split
vent
178
Note that the GC reports flows calibrated to 25 °C and
1 atmosphere. Correct flowmeter results accordingly.
Hydrogen (H2) is flammable and is an explosion hazard when
mixed with air in an enclosed space (for example, a flow meter).
Purge flowmeters with inert gas as needed. Always measure
gases individually. Always turn off detectors to prevent
flame/bead autoignition.
Septum purge and split vent flows exit through the pneumatic
module at the top rear of the GC. See the figure below.
To measure split vent or septum purge flows, attach the
flowmeter to the appropriate tube. Remove the GC pneumatics
cover to access the back inlet exhausts.
Back inlet purge
vent
Front inlet
purge vent
Agilent 7890 Series Troubleshooting