My tune reports on my GC 6890N/5973 MSD have been really noisy/low sensitivity. My source is clean and I don't know what else it could be. Leak maybe?

Hello xio,

the case is a bit older: do the problems still exist?

If so, a new tune report would be more than helpful.

small hint to the first tune report (24th July):
a) If the H20 value is too high (e.g. like in the first 1-2h after pump down: the H20 value is gigantic) then usually the N2/O2 is also very high, WITHOUT a leak!
Therefore: if the H2O value is higher than 5-10%, first look for the cause of the water reason.

Pump down: after one night the H2O value is usually less than 3(-5)% if the MSD is supplied with column flow.
If the MSD is NOT supplied with carrier gas (blind sealed) the MSD needs much longer to pump down the H2O from the MSD; here I have seen several days higher H2O values.

b) Number of peaks=512
this value is also MUCH too high.

it could also drop to a normal level 100-150 peaks if the H2O value is at a normal level

regards, M.

Hello xio,

the case is a bit older: do the problems still exist?

If so, a new tune report would be more than helpful.

small hint to the first tune report (24th July):
a) If the H20 value is too high (e.g. like in the first 1-2h after pump down: the H20 value is gigantic) then usually the N2/O2 is also very high, WITHOUT a leak!
Therefore: if the H2O value is higher than 5-10%, first look for the cause of the water reason.

Pump down: after one night the H2O value is usually less than 3(-5)% if the MSD is supplied with column flow.
If the MSD is NOT supplied with carrier gas (blind sealed) the MSD needs much longer to pump down the H2O from the MSD; here I have seen several days higher H2O values.

b) Number of peaks=512
this value is also MUCH too high.

it could also drop to a normal level 100-150 peaks if the H2O value is at a normal level

regards, M.