Chromatography Forum

I want to ask if someone can help me with my problem. I work on GC -FID equipped with Tekmar autosampler and i can't see peaks. The problem shold be with autosampler becauase when i inject the solution manual i take the peaks. I have this problem after cleaning the autosampler using high temperature on loop and transfer line. Can be because of contamination in any part of the Tekmar? The test for the leak check passes. Any idea?

We need more information. Sounds like a pressure loop type headspace autosampler with stardard cut inlet carrier gas feed isntallation or septa needle? Could be a bad valve?

I want to ask if someone can help me with my problem. I work on GC -FID equipped with Tekmar autosampler and i can't see peaks. The problem shold be with autosampler becauase when i inject the solution manual i take the peaks. I have this problem after cleaning the autosampler using high temperature on loop and transfer line. Can be because of contamination in any part of the Tekmar? The test for the leak check passes. Any idea?

Which model ? !!!
How do you know the problem is with autosampler, not with concentrator ?

Also check the needle and headspace vial position/septa. I had some septa that were apparently to concave or something where the needle did not completely penetrate it into the septa. I have a Tekmar 7000