Hello to everybody,
Presently i am using PFPD detector with Varion-450 Gc having Galaxie software.
i am analyzing the presence of sulfur in the refrigarent gases and i got the peak .
My querry is actually regarding the refrigarent gas peak which i was getting in the negative side and the sulfur peak is in positive side.
we are using the Helium as carrier gas.also i would like to know how we can change the PFPD From sulfur to Carbon or nitrogen mode.

please help me and suggest .