agilent 6890 vs 7890 with 5975 MSD - running H2

[FlavorsYum]

Looking to purchase a GCMS system - any advice on advantages/disadvantages on 6890/7890 for performance/maintenance/operations/capabilities etc. other than the obvious cost difference? Any advice on setting up a "new-used" system to run H2 as the carrier?

Thanks in advance!

[Steve Reimer]

Check with Agilent about H2 carrier gas with MS. They have specific parts requirements for the source.

[MSCHemist]

The 5975 needs a drawout plate with a larger aperture for H2 and some 5975's have a magnet in the source with no serial number on it that needs to be replaced for H2. Other considerations are you should probably get a performance turbo to efficiently pump H2.

Any Agilent GC should do hydrogen fine even a 5890 not that you would consider one. Don't inject chlorinated solvent or you could get HCl gas in the system.

[FlavorsYum]

Thanks for the really helpful advice. After seeing these posts, I picked up a copy of some recommended Agilent procedures for running H2 carrier gas. For now, I think I will stick with He...