Victaulic FireLock NXT 776 Series - Page 23

16a. If pressure in the diaphragm charge line drops, the
diaphragm must be replaced and/or any leaks in the
diaphragm charge line must be corrected. Refer to the
“Removing and Replacing the Diaphragm Assembly” section.
16b. If pressure in the diaphragm charge line does not drop,
re-open the diaphragm-charge-line ball valve, and proceed to
the following step.
17. FORPNEUMATIC(DRYPILOT)RELEASESYSTEMS: Observe the
system air pressure over a 24-hour period to confirm system integ-
rity. If there is degradation in system air pressure, find and correct
all leaks. NOTE: NFPA requires less than 1½-psi/10-kPa/0.1-Bar
leakage in 24 hours.
18. Open the water supply main drain valve.
CAUTION
Takeprecautionswhenopeningthewatersupplymaincontrol•
valve,sincewaterwillflowfromallopensystemvalves.
Failuretofollowthisinstructioncouldresultinpropertydamage.
Water Supply Main
Control Valve
19. Open the water supply main control valve slowly until water flows
steadily from the open water supply main drain valve.
20. Close the water supply main drain valve when a steady flow of
water occurs.
21. Confirm that there is no leakage from the intermediate valve
chamber. The drip check in the alarm line should not be leaking
water or air.
I-769D_21
FireLockNXT™DelugeValve
SERIES 769
I-769DINSTALLATION,MAINTENANCE,ANDTESTINGMANUAL
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VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D