How to diganose water leak in GC-MS?  15% water, 7% nitrogen.

Hi chemist23,

I would check gas trap to see if saturated. My guess is that the carrier gas may have moisture in it. Is this hydrogen carrier?

Regards

James

Most of the filters are purged with N2 when they are packed. Usually some moderate flow through the trap will see the N2 reduce over time. Depending on the trap and total flow this could be a short period of time to longer if you are using the large capacity traps.

Regards

James

Thanks, It turned out the gas filter was saturated. Replacing the gas filter solved the problem. 

After purging the new gas filter for 4 minutes @ 400ml/min, I still receive a high nitrogen reading ~50%. Is there a way to reduce the N2 reading faster or does the MS vacuum need to be left overnight?

When I install a new Gas Clean filter, I set the split flow to 200-250 mL/min and leave it overnight.  Typically the N2 is below 10% the next day.

If I'm trying to get rid of nitrogen from my system after air water check what is the most practical way to do it?

Is it only Nitrogen in the background?  What is the Nitrogen to Oxygen ratio?   Dry air contains 78% nitrogen and O2 is 21%...so it looks like ~4:1 ratio.  If there is Nitrogen but no, or little, oxygen, then either there is nitrogen in your gas supply or a leak before an oxygen filter that is removing the oxygen.

Please share back a screen capture of the air/water check and a current autotune report, too.