TM 10-4610-232-12
2-24. ROUTINE OPERATION.
a. Production Rate. Operate the ROWPU to keep the storage tanks full without overflowing as follows:
(1) Set the operating pressure to obtain the mission normal water flow as described in para. 2-17b(4). The mis-
sion normal water flow (shown in gpm on Tables 2-18 and 2–20) will average the daily gallons of production as listed
over a 10 day mission. The 10 day mission profile provides 200 hours of water production and 40 hours as follows:
Set-up/tear down and transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 hours
Off-line generator PMCS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 hours
Maintenance allowance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 hours
Filter backwash, cartridge filter element changes
and strainer changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 hours
RO element cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 hours
40 hours
CAUTION
Operating at push limit may damage RO elements and require more frequent
cleaning.
NOTE
To achieve the daily average production, the ROWPU is operated continuously at
mission normal flow rate (Tables 2–18 and 2–20) and only shut down as needed for
routine services and scheduled maintenance. If needed to meet mission demands,
higher water flows may be obtained under push conditions.
(2) Operate under push conditions by increasing the pressure to provide any required water flow up to the limiting
flow to meet mission demands. Operating at push conditions for up to 10 hours between routine cleanings does not
require repeated procedures. Operating at push conditions for extended periods may cause fouling and scaling which
will require extended cleaning. (See para. 2-25 and 2-26, ) After a 24 hour maximum push to meet an emergency, a
routine hot detergent cleaning should be carried out, if mission demands allow.
(3) The ROWPU maybe shut down to stand-by when the tanks are full.
(4) The flow of product water from the ROWPU can be decreased by decreasing system operating pressure.
Decrease system operating pressure by further opening the pressure control valve. This is preferred over constantly
stopping and starting the ROWPU when water demand is low. Constant starting and stopping stresses the equipment
and may cause damage to the motor starters.
b. Routine Operational Services. Perform the following services as indicated by t he number of operating hours, or by
the warning horn and yellow warning lights. Table 2-27 provides a summary.
NOTE
There are two horns which will come on when certain conditions occur. The warning
horn has a pulsing sound; the alert horn has a steady sound. The warning horn will
sound when chemical levels are low and when there is high differential pressure in
the basket strainer or filters. The alarm horn will sound when the clean/flush tank
level is low, feed pressure is low, product pressure is high, or high pressure pump
pressure is too high. Yellow warning lights go on with the warning horn. Red alarm
lights go on with the alert horn and the ROWPU shuts down, except for the clean/
flush tank low alarm. It causes a shutdown only in clean mode.
(1) Backwash media filter. See para. 2-21 for instructions.
l At least once each day.
l Every six hours on rivers and lakes with a lot of organics, where turbidity is over 15 NTU and temperature
is over 70°F (21°C).
l Whenever media filter outlet turbidity increases by more than 0.5 NTU over lowest reading since last
backwash.
l Whenever the MEDIA FILTER PLUGGED light and warning horn go on.
l Whenever the pressure drop reading is over 25 psi (172 kPa). (Warning light and horn should come on.)
(2) Check filter performance and keep optimized if polyelectrolyte is being used.
(a) Record the media filter outlet turbidity at 1 hour intervals and note the time and polyelectrolyte pump settings
on the Media Filter Log as shown on Figure 2-55 (Media Filter Log forms to be reproduced locally are contained in
Appendix H). Also note the time of each backwash. This log provides information essential to the best operation of the
ROWPU.
Change 2 2-105
