TM 10-4610-240-10
TM 08580C-10/1
T.O. 40W4-13-21
(10) Start element cleaning. Push ELEMENT CLEANING switch (figure 2-4) up to START position. Release
switch. Switch automatically goes to RUN position. Element Cleaning starts.
NOTE
If element cleaning does not start, it may be necessary to loosen vent plug on backwash pump to
purge air. Tighten vent plug when pump is primed.
(11) Within a few seconds, BRINE FLOW indicator (17, figure 2-4) should show a flow of 16 gpm or more.
CAUTION
If pH of water circulating through R. O. elements drops below 3.5, element membranes may be
damaged.
(12) After five minutes, check pH (paragraph 2-15) of water discharging back into brine tank; it should be near,
but not below, 3.5. If it isn't, add another pound of citric acid and stir until all granules are dissolved.
NOTE
If in past, when using the same source water, brine has been very alkaline, then more citric acid may
be added at a time; however, in no case should the pH of the water circulation through R.O. elements
drop below 3.5.
(13) Continue checking pH and adding lib of citric acid at 5 minute intervals until pH of water is near, but not
below, 3.5.
(14) Allow citric acid solution to circulate for 45 minutes. Periodically check the temperature of the water
discharging back into brine tank; use thermometer in Storage Box No. 2.
CAUTION
Temperature of solution will rise during element cleaning. At no time should it exceed 120 degrees.
If temperature rises above 120 degrees, stop recirculating citric acid solution, and resume normal
operation.
(15) Stop recirculation by pushing the ELEMENT CLEANING SWITCH down to OFF.
(16) Remove VENT VESSELS hose from outlet of the backwash pump and connect backwash water hose to
backwash pump outlet.
WARNING
Drainage lagoon should be located down stream from unit.
(17) Drain citric acid solution into a shallow man-made lagoon a reasonable distance away from the unit. Close
valve at discharge of brine water tank (figure 2-66).
(18) Perform startup procedures for normal filtering operation (paragraph 2-9).
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