Chromatography Forum

Dear all

good morning

I am doing an analysis of methyl acetate on an Agilent 6890 using Helium as carrier gas (FID detector) using the GC injector. I am observing continuous spikes in the chromatogram. I have baked the column overnight, checked the inlet septa, cleaned the jet plug and ensured there are no leakages. What could be the reason and how can i avoid it ?
Other GC instruments connected to the same gas lines do not give this problem. It is specific to one particular instrument, the one that i am using.

Thanks and regards
Dinesh

Are the spikes still there if you do a blank run with no injection ?

Are the spikes there during standby ?

Are the spikes there if you turn the flame off. ?

Remove the column from the detector and plug the connection - are the spikes still there ?

Peter

What kind of column are you using?

best wishes,

Rod