6890 N inlet pressure not ready

6890N I am having an issue with GC Not Ready Front Inlet Pressure Not Ready.  The pressure overshoots by about 0.5 psi in both directions and won't stabilize.  The autosampler won't make the injection because of the not ready condition.

Column 30 m x 0.25mm x 250 um.  1 mL/min Split 20:1 Constant Flow Pressure 18.4 (goes back and forth between 17.9 psi and 19.0 psi)  Total Flow 20.1  Could it be ECP?  I haven't had issues before.

  • Hi

    Replace septa and split vent filter.

    If still problem persist then swap EPC from back to front to confirm EPC issue.

    And if you want then you can do pressure test also.

  • What ISH said in the first instance - check for obvious leaks (septum / septum head fitting / cracks in a column). Then consider both the S/SL EPC (possible dodgy proportional valve which you can swap from another EPC / PCM) or a possible dodgy prop valve at the Split Vent too (which again could be replaced / swapped). You'll find the split vent / EPC prop valves have white / black tape around the coil indicating which type they are. P/N's are also on those parts too buy I don't think you can order them directly.

Was this helpful?