What is causing these baseline deviations on the TIC?

Hi

First check column n inlet of GC..

If still problem continue then MS preventive maintenance require...

Thank you for the reply.  What am I checking for with the column and inlet?  I'm guessing there is some kind of contamination but I don't know what to do to get rid of it.

Gas sampling valve is connected with inlet of GC or directly from valve sample is going in column.

Are you using capillary column or packed column?

Injection split /splitless or direct?

Caplilary, split/splitless injector.  Should I condition the column with the end removed from the MS? Or is it ok to leave everything connected while conditioning?  There is two columns, the other one goes to a TCD/FID.

Yes..should be remove from ms and ms should be capped with blank nut otherwise all contamination of column will go to MS.

Injector( split/splitless) septa, liner n gold seal should be checked/replaced to avoid  contamination

Vent the MS before removing column end and conditioning?  I don't have any blank nuts unfortunately.

Yes..u have to vent it..

Ok, I've tried to condition the column three times and no improvement.  I also have clipped some of the inlet end of the column and reinstalled and that did not help either.  I have not checked inlet as I have not worked on them before and I don't have supplies to change the septa, liner and seal.  We don't use the injection ports at all, only the gas sampling valve.  The gas sampling valve injects the sample onto both columns at the same time.  It seems odd to me is that we have two columns connected to the same sampling valve and only seeing the abnormal baseline from the column that goes to the MS.  The other column which goes to a TCD and then FID is normal and not showing any baseline deviations.  If contamination was in the inlets or sampling valve wouldn't it show up at both detectors (the MS and the TCD/FID)?  Also there are no unusual fragments in the mass spectra other than the typical ones associated with air (17, 18, 28, 32).

Ok, I've tried to condition the column three times and no improvement.  I also have clipped some of the inlet end of the column and reinstalled and that did not help either.  I have not checked inlet as I have not worked on them before and I don't have supplies to change the septa, liner and seal.  We don't use the injection ports at all, only the gas sampling valve.  The gas sampling valve injects the sample onto both columns at the same time.  It seems odd to me is that we have two columns connected to the same sampling valve and only seeing the abnormal baseline from the column that goes to the MS.  The other column which goes to a TCD and then FID is normal and not showing any baseline deviations.  If contamination was in the inlets or sampling valve wouldn't it show up at both detectors (the MS and the TCD/FID)?  Also there are no unusual fragments in the mass spectra other than the typical ones associated with air (17, 18, 28, 32).

Okay..

Then i will suggest to call your local agilent support to check it onsite..

Meanwhile, can you share autotune report of MS..

I decided to try switching filaments.  I switched to filament 2, did an auto tune and baseline is normal.  I guess filament 1 needs to be replaced!

Gr8....