Retenton time shifts

[thohry]

I am analyzing CO by GC 6890 on the Carbon Plot column. The problem is after about 1 month, the retention time is approx. 1 minute earlier, and only CO. I have to recalibrate quiet often. Can anyone explane to me and how to overcome this. Thank you.

[larkl]

I haven't used the carbonPLOT, but other PLOT columns will show a shift to shorter RT as the column absorbs moisture etc. from the carrier. Does a bakeout shift the RT back?