LOW PRESSURE READING

TM 10-1670-265-12&P

T.O. 13C7-1-21

4-17. ASPSU - Test (Cont)

4-17

TESTING (Cont)

2. Operational test procedure (Cont).

c. Testing (Cont).

LOW PRESSURE READING

(9) Return ASPSU TEST switch (6) to the OFF

position. Turn PUMP switch (3) to the off position.

(10) Place PRES. DUMP switch (12) to the up

position to depressurize chamber.

(11) Place AC POWER switch (1) to the OFF

position.

WARNING

Always insure that the ASPSU test set is

depressurized before attempting to open chamber

door as personnel injury may result.

(12)

Raise the ASPSU test set pressure

chamber door.

(13) Return ALT. DECR. switch (11) to the

down position. Place the PRES. DUMP switch (12) to

the down position.

(14)

Set BARO. PRES. switch on ASPSU to

29.5.

(15) Close the pressure chamber door.

(16) Repeat steps cl through c9 above and

record the altitude at which the FIRE indicator lights.

NOTE

Fire altitudes and recorded data will reflect a difference

in altitude relative to the initial altitude checks. This

difference should correspond directly to the difference

between 29.9 and 29.5 inches of mercury or an increase

in FIRE altitude of +400'±250'for altitudes of 9,900' to

5,000' and +400' ±150' for altitudes of 4,900' to 100'.

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