The software includes illustrated tutorials for sophisticated procedures like analyzer calibration.
On page 112 (yes, I bookmarked it), the manual shows a diagram. You screw it until you hear a hiss , then back it off half a turn. If you screw it all the way, you puncture the seal too early, and all the gas vents out before you even attach the hose. gfs-3000 manual
Additionally, WALZ has a support portal ( support.walz.com ) with firmware and scanned manual pages for legacy units. I bookmarked it)