HP 5890 Series II Plus Reference Manual page 161

Preventive Maintenance
Packed column inlet
4. Fully open the mass flow controller counterclockwise and wait 1 to
2 minutes to ensure equilibrium.
5. Turn off gas to the inlet at its source.
6. Wait 10 minutes while observing carrier source pressure. If it drops
less than 7 to 14 kPa (1 to 2 psi), the system (through the inlet
column fitting) is considered leak free.
Evidence of leakage requires the inlet system be leak•checked.
Repressurize the system as necessary, and
Use a suitable leak•detectionfluid to check for leakage fittings.
Correct or replace leaking fittings as needed.
Leak•detectionfluids often leave contaminating residues; after each
Caution
application, the area checked should be rinsed with CH
and allowed to dry.
After verifying fittings are leak•free,there are two locations at the
inlet itself where leakage may occur: at the septum, and at the
column connection.
-
-
The column connection is checked using a leak•detectionfluid.
The septum is checked with a bubble flow meter by pressing its
rubber inlet tube tightly onto the needle entrance in the septum
retainer nut or simply replacing the septum.
OH (methanol)
3
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