I-768N
/ Series 768N FireLock NXT
™
Dry Valve
/ Installation, Maintenance, and Testing Manual
6.
Replace the diaphragm with a new, Victaulic-supplied diaphragm.
Align the holes in the diaphragm with the holes in the valve
body. Use caution to prevent damage to the diaphragm during
installation.
7.
Align the holes of the diaphragm cover with the holes in the
diaphragm/valve body. Tighten all cap screws into the diaphragm
cover/valve body in an even, crossing pattern to a torque of
10 ft-lbs/14 N•m. Repeat this tightening sequence to verify that all
cap screws have been torqued to 10 ft-lbs/14 N•m.
8.
Re-attach the trim at the unions that were loosened in step 2.
Refer to the applicable trim drawing for details.
VERIFY THAT
ALL UNIONS THAT WERE LOOSENED TO PERMIT ACCESS TO
THE DIAPHRAGM COVER HAVE BEEN RE-TIGHTENED BEFORE
ATTEMPTING TO PLACE THE SYSTEM BACK IN SERVICE.
9.
Place the system back in service by following the “Resetting the
System” section. Inspect all trim components to confirm that
there are no leaks. Any leaks must be corrected immediately
by depressurizing the system and tightening any affected
components.
CLEANING THE CARTRIDGE IN THE AIR AND
PRIMING MANIFOLD ASSEMBLIES
1.
Remove the system from service by following steps 1 – 10 of the
“Required Internal Inspection” section.
2.
Remove the existing cartridge from the air manifold and priming
manifold assemblies, shown above. Rinse the cartridges to remove
any deposits.
3.
Install the corresponding cartridge into the air manifold and
priming manifold assemblies.
NOTE:
The face of the air manifold
cartridge is stamped “AM” and the face of the priming manifold
cartridge is stamped “PM.” These cartridges are designed so that
they cannot be interchanged.
4.
Place the system back in service by following the “Resetting the
System” section.
REPLACING THE FILTER IN SERIES 776
LOW-PRESSURE ACTUATORS
1.
Remove the system from service by following steps 1 – 10 of the
“Required Internal Inspection” section.
2.
Remove the Series 776 Low-Pressure Actuator from the trim. Refer
to the applicable trim drawing for details.
3.
Remove and discard the filter.
CAUTION
• DO NOT re-use filters. After removal, the old filter must be
replaced with a new, Victaulic-supplied filter.
Failure to follow this instruction could cause improper valve
operation, resulting in property damage.
4.
Use only a new, Victaulic-supplied filter. Install the new filter
onto the filter adapter, as shown above. Make sure the o-ring is
positioned on the filter adapter, as shown above.
5.
Carefully re-install the filter adapter into the actuator. Use caution
to prevent damage to the o-ring.
6.
Re-install the actuator into the trim. Refer to the applicable trim
drawing for details.
I-768N_31
REV_C
