Step 8.
Purge night vision goggle by pumping vacuum handle until purge device gauge
indicates greater than 20 inches of Hg.
Step 9.
Position purge device LEAK TEST/PURGE switch (10) to LEAK TEST and
observe that the purge device gauge (9) indicates a steady vacuum reading of 20
inches of Hg or higher. If unable to observe a steady vacuum reading, a leak is
present. Stop purge procedure and seal night vision goggle leak(s). If purge
device gauge (9) indicates a steady vacuum reading, position purge device LEAK
TEST/PURGE switch (10) to PURGE.
Step 10.
Set purge device PUMP/NITROGEN switch to NITROGEN and observe that the
purge device gauge indicates 3 PSI.
Step 11.
Position purge device LEAK TEST/PURGE switch (10) to LEAK TEST and
observe that the purge device gauge (9) indicates a steady pressure reading of
3 1 PSI. If unable to observe a steady pressure reading, a leak(s) is present.
Stop purge procedure and seal night vision goggle leak(s). If purge device gauge
(9) indicates a steady pressure reading, position purge device LEAK
TEST/PURGE switch (10) to PURGE.
Step 12.
Repeat steps 8 and 9 four additional times.
Step 13.
Close purge screw with adapter handle. DO NOT OVER-TIGHTEN PURGE
SCREW.
Step 14.
Set purge device (8) PUMP/NITROGEN SWITCH (11) to PUMP and LEAK
TEST/PURGE (10) switch to PURGE.
Step 15.
Remove purge adapter and replace purge cover.
Step 16.
Prepare for continued purge/fill procedure or turn off nitrogen tank valve and
remove and store fire control tool set and purge device.
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