AnsweredAssumed Answered

GC/MS inlet pressure and column flow fluctuate

Question asked by d.monis on Jul 29, 2019
Latest reply on Jan 14, 2020 by matthew2

Hi everyone!

I have problems with the flow and pressure of my gas chromatograph.

Working with a gas chromatography equipment (Agilent 6890N) coupled to a mass spectrometer (Agilent 5973) and both the flow and the pressure  fluctuate and do not stabilize, after doing an internal leak test of the injector, it gives us positive, we have changed everything and still the problem persists. The consumables we have changed are:
-Cu tubing from Splitless
-Sector injector
-Liner Splitless: Gold Plated Inlet Seal with Washer, injector line septum.
-DB-5 GC column was cut in both extremes, inlet and MS line zones, in case there was any obstruction. At the same time, fittings and correspondent graphite ferrules were replaced.
-Split Vent Trap

Do you know where the problem may come from?

I know that I can use Argon gas as an indicator of leaks, but I would not know exactly how to do it, if you could also indicate that it would be of great help


Thank you!