11. Disconnect the line from the LOW
PRESSURE connection and REF. TAP in the
altitude chamber. Disconnect the regulator outlet
from N2 INPUT connection, and remove the plug
from the piezometer.
12. If excessive leakage is indicated, locate the
probable cause by using troubleshooting chart,
table 12-5A.
Outlet Leakage Test
To perform an outlet leakage test, proceed as
follows:
1. Place the regulator supply valve control
lever in the ON position.
2. Ensure that the diluter control lever is in
the 100-percent OXYGEN position.
3. Place the emergency pressure control lever
in the NORMAL position.
4. Mount the regulator on a horizontal plane
in the test chamber. Connect the regulator inlet
to the N2 INPUT connection (18) inside the
altitude chamber.
5. By using the LOW PRESSURE REG-
ULATOR, apply 150 psig to the regulator inlet.
6. Slowly turn the INLET PRESSURE
ON/OFF valve to ON.
7. Activate the emergency pressure control
lever to allow a flow through the regulator, then
return the lever to its NORMAL position.
8. Draw a film of leak detection compound
(MIL-L-25567) across the regulator outlet. The
film should not advance more than 1/2 inch in
10 seconds. If the film advance is more than
allowable, repeat the test three or four times.
(Distention could be caused by difference in
temperature between inside and outside of
regulator.)
9. If the film advance continues to be more
than allowed, locate the probable cause by using
the troubleshooting chart, table 12-5B.
10. Relieve pressure on the regulator by back-
ing out on the LOW PRESSURE REGULATOR.
OXYGEN SUPPLY VALVE LEAKAGE
TEST.— If the supply pressure could not be shut
off, until a demand was placed on it, a pressure
buildup could be created. It could damage the
regulator hose or mask and possibly injure the
crewmen. To perform the oxygen supply valve
leakage test with the regulator still mounted in the
chamber, proceed as follows:
1. Place the regulator oxygen supply valve
lever in the OFF position.
Table 12-5B.—Troubleshooting (Outlet Leakage Test)
12-11
