Gas connection leaking / Coupling leaking
The gas lines from and to the OPTIC inlet body have a connector on a distance of about 35 cm from the inlet. The tubing's are labeled with P (Septum Purge), S (Split) and C (Carrier). Make sure when connecting the coupling an aluminum sealing ring (p/no 2406-2056) for this joint is used to ensure the leak tight connection.
Use two 10 mm spanners to tighten the couplings.