TM 55-2090-201-14&P
3-38. FILTER ELEMENT (#) (Continued).
LOCATION
ITEM
ACTION
REMARKS
1. Perform differential pressure calculation as follows:
The pressure differential in the first stage prefilter (2) is ob-
tained by subtracting the first stage pressure (3) from the inlet
pressure (1).
Example:
40 psi (2812.3 gm sq cm) inlet pressure
- 25 psi (1757.7 gm sq cm) first stage pressure
15 psi (1054.6 gm sq cm) differential in first
stage prefilter
Replace the pre-filter element when the pressure differential is
more than 30 psi (2109.2 gm sq cm).
The pressure differential in the second stage separator (4) is
obtained by subtracting the second stage pressure (5) from the
first stage pressure (3).
Example:
35 psi (2460.7 gm sq cm) first stage pressure
- 25 psi (1757.7 gm sq cm) second stage pressure
10 psi (703.0 gm sq cm) differential in second stage
separator
Replace the coalescer element when the pressure differential is
more than 25 psi (1757.7 gm sq cm).
The pressure differential in the third stage separator (6) is
obtained by subtracting the outlet pressure (7) from the second
stage pressure (5).
Example:
20 psi (1506.0 gm sq cm) second stage pressure
- 5 psi (351.6 gm sq cm) outlet pressure
15 psi (1054.4 gm sq cm) differential in third stage
separator
Replace the coalescer element when the pressure differential is
greater than 25 psi (1757.7 gm sq cm).
NOTE
The pressure differentials for the other stages may
be obtained in the same manner by using the appro-
priate pressure gauges.
3-236
