Agilent Technologies Agilent 7890 Series, Maintenance Manual

Page: 342 / 354

342 Maintaining Your GC
19
Maintaining a Valve
6
Remove the upper valve box. (See “To Remove the Upper
Valve Box” on page 344.) Vacuum any RCF insulation
particulates from the valve box area.
7
Note the tubing connections to the existing valve and
label if desired.
8 Disconnect the existing valve fittings.
9 Remove the two T- 10 Torx screws attaching the valve to
the valve box, then remove the valve from the valve box.
10
Place the new valve in the valve box. The gap in the
index ring on top of a 6- port valve points toward the
back of the GC if installed correctly. This is the
On
position. Install and tighten the two screws with a
screwdriver.
11
Use needle- nosed pliers to move the valve rotor index pin
of the valve counterclockwise until the pin touches the
valve stop
Off position.
WA R N I N G
The valve box insulation is made of refractory ceramic fibers
(RCFs). To avoid inhaling RCF particles, we recommend these
safety procedures:
1. Ventilate your work area
2. Wear long sleeves, gloves, safety glasses, and a disposable
dust/mist respirator
3. Dispose of insulation in a sealed plastic bag
4. Vacuum any residual particles and discard
5. Wash your hands with mild soap and cold water after handling
RCFs.