GC (7890A) - MS (5975C)
I am observing high column bleed and cannot locate the source of the problem (see photo attached).
I have checked for an air leak (see tune reports attached, before and after the problem arose) and no leak appears to be present.
I have then cleaned the inlet port, tried a column bakeout, run over 10 blank samples and cut ~10 cm off the front of the column but the problem still persists.
This column is only 3 months old.
Can anyone suggest any other things I can do to locate the source of the problem before I requets an enigneer to come and take a look?