GC-FID

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chemguy99
chemguy99's picture
GC-FID

I am troubleshooting our GC-FID and have a problem.  When we inject a 1uL sample, we do not see any sample peaks at the detector including the solvent.  I have leak checked the inlet and found no leak.  Also, I have replace the inlet liner, septa and gold seal with same result.  I remove the column from the inlet and injected the sample directly into the column and placed the column back in the inlet.  The peaks are then present at the detector.  I am wondering if anyone else has had this problem.  I think maybe the electronic component that controls the valve for split/splitless valve is bad?  Thanks for your help.

Dr. Analytical
Dr. Analytical's picture
Please indicate the model of

Please indicate the model of GC, column dimensions, and inlet settings.

Try setting the inlet to split mode only, with a split ratio of 10:1.  Check the flows through both the column and split vent.  Do an injection and see if the solvent peak is present.  Try changing the split ratio to see if the size of the solvent peak changes.