TM 55-1925-282-14&P
0005 00
MEDIA FILTER BACKFLUSH
NOTE
Always perform the media filter backflush procedure before and after all ROWPU op-
erations. If differential pressure exceeds 20 PSI (1.4 bar) as indicated by the difference
between the media filter INLET PRESSURE and OUTLET PRESSURE gauges, secure
ROWPU operation, and perform media filter backflush.
1. CLOSE the following valves:
a. RO-V-2 (figure 8, item 2), media filter supply.
b. RO-V-3 (figure 8, item 3), media filter discharge.
c.
RO-V-1-1 (figure 9, item 3), ROWPU 1 inlet sea water supply.
d. RO-V-2-1 (figure 9, item 4), ROWPU 2 inlet sea water supply.
e. RO-V-4 (figure 8, item 4), media filter bypass.
f.
RO-V-5 (figure 9, item 5), cleaning supply.
g. RO-V-11 (figure 8, item 5), media filter drain.
2. OPEN the following valves:
a. RO-V-10 (figure 8, item 6), media filter backflush valve.
b. RO-V-1 (figure 8, item 1), main sea water supply.
3. Verify that RO-PG-1 (figure 8, item 7), general service pressure, indicates a minimum of 30 PSI (2.4 bar).
! CAUTION
Media tank inlet pressure must not exceed 45 PSI (3.1 bar) and differential pressure
must not exceed 35 PSI (2.4 bar), or damage could occur to the media filter tank.
4. Align the media filter maintenance mode valves (figure 9, item 6) to the "BACKWASH" position as shown in
figure 12.
5. Slowly OPEN RO-V-2 (figure 8, item 2), media filter supply, to backwash the media filter.
6. Verify that the media filter INLET PRESSURE gauge (figure 9, item 7) does not exceed 45 PSI (3.1 bar).
7. Verify that the pressure differential between the media filter INLET PRESSURE gauge (figure 9, item 7) and
the media filter OUTLET PRESSURE gauge (figure 9, item 8) does not exceed 20 PSI (2.4 bar).
8. BACKWASH the media filter for a minimum of 10 minutes, or until differential pressure between the media
filter INLET PRESSURE gauge (figure 9, item 7) and the media filter OUTLET PRESSURE gauge (figure 9,
item 8) is less than 5 PSI (0.3 bar).
9. CLOSE RO-V-2 (figure 8, item 2), media filter supply.
10. Align the media filter maintenance mode valves (figure 9, item 6) to the "RINSE" position as shown in
figure 12.
0005 00-9
