Chromatography Forum

I am running a 5973/6890 as a new install. I ran a linear gradient from 40 to 300 over 54 minutes. about halfway thru
the run the peaks on the MS side start broadening badly and after 30 minutes come out as one wide hump.
I have never run without the thermal aux to the MS side. Is this due to adsorption in the transfer to the MS?
Can a thermal aux be added?

Thanks!
Marc


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Define what top and bottom chromatograms are.

What is your MSD temperature?

Thanks CPG. Top is MS and bottom is FID. Running post-column split. Quad is 150 and source is 230.

I never connected the aux heater cable. Vented and connected and now working fine.

FYI the aux setting is what heats the transfer line. Before you connected it you were condensing sample after the GC oven. Did you cut the portion of the column that was in the transfer line when you vented?