Valve Actuator Alignment - Agilent Technologies 7820A Service Manual

246
Agilent 7820 GC Service
Hazardous voltages are present when the GC
electronics are exposed.
Reinstall the actuator solenoid bracket to the GC.
Connect the GC power cord and turn on the GC.
Press the switch under each solenoid to activate it and
pressurize the system.
The solenoid valve replacement is complete. If no other
accessories or parts require installation, reinstall all GC covers.

Valve actuator alignment

1 Remove the valve box top assembly. See steps 1 through 3
of Removing the valve box assembly (238) for the
procedure.
Loosen the actuator link arm lock screw at each actuator with a 3
mm hex key wrench so that the coupling/shaft assembly is free
to rotate. Push the coupling shaft fully into the actuator.
Turn the valve rotor index pin of each valve counterclockwise
until it is 0.010 inch (0.25 mm) from the counterclockwise
(left-hand) valve stop.
Reinstall the valve box top assembly.
Gently rotate and push the coupling/shaft assembly with a
blade-type screwdriver until the slot on the coupling fully
engages the valve rotor index pin. Repeat this procedure for
each valve installed.
Use care in performing the following operation so
as not to accidentally turn the valve rotor away
from its preset (step 3) position.
Make sure that all solenoid valves are turned "off" by the
appropriate valve controller. Turn on the air supply to the
solenoid valve(s). The piston rod of each actuator will move all
the way out to the extended (OFF) position. Very firmly tighten
the link arm lock screw for each actuator.
Install the hardware for any variable restrictors present.