EX RGA tree was noted to be leaking, see alogs 55538 & 55662

While EX was vented we helium leaked checked all of the CF connections on the tree, with 4 found to have leaks all in the E-9 range likely formed during bakeout as much of the flanges/hardware were discolored from overheating (helium background ~2E-10 Torr-l/s).

The RGA tree was vented and the leaking joints replaced. The PrismaPlus RGA was aslo found to have a burned/broken filament, so it was replaced with a new PrismaPro RGA. This will have to integrated into the Vac controls rack, so we can operate the RGA from the control room RGA computer, for now scans will be collected locally.

We also took this opportunity to add a 10 l/s maintainer ion pump on the RGA tree with a 2.75"CF angle isolation valve. After pumpdown with an Aux cart, the ion pump was plugged in and tested before bakeout. Next the whole tree will be wrapped with heat tape and baked out.

Old RGA tree and rebuilt tree pictures attached.