Column flow/pressure drops during desorb

Hi everyone 

I am new in this platform and i am hoping to learn more. 

I recently removed my column and trimed it but when i replaced it back i have experienced the following: immediately after purge and trap desorbs the column flow drops for the set time of desorption. The tune report has passed. I have change the liner, gold seal, and septum but doesn't help the situation. 

I have been doing this same exercise(trimming) before when i was still using the chemstation software. Now the software is changed to mas hunter and since then we have been experiencing problems. Part of the other problem is that the pulsed plit injection doesnt work anymore. 

Could this dropping of column flow be connected to the software upgrade or it is a hardware problem? And what could it be? 

  • Can you share some screen captures from MassHunter Acquisition with your run method loaded of the  Inlets SSL-Front (or whichever one your P&T is connected to), GC Columns window, the Configuration/Columns window, and the Configuration/Modules window?   It could also be an issue inside the P&T. During desorb a valve inside the P&T puts the trap inline with the flow to the inlet while the trap heats up to desorb your compounds. If the valve is not working right, the trap is plugged or leaking, or a few other possibilities, the pressure/flow to the GC inlet won't be present.  

    Does the GC work fine without running the P&T?  If you just setup and start a run by pressing the start button, does it run?  

  • Hi again. When i start a run by pressing  the start button it doesnt drop down. But when i try with a different sample introduction(G1888) it drops. But the peak shape and background noise is better this time around.

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