TM 10-4610-240-10
TM 08580C-10/1
T.O. 40W4-13-21
c. Normal Backwash.
(1) Shut the ROWPU down in the normal way (paragraph 2-14).
(2) Make sure R.O. ELEMENT CLEANING switch (figure 2-4) on side of control panel is down (off).
(3) Check water level in brine water tank. Tank should be full.
(4) Ensure basket strainer in backwash pump is not clogged.
(5) Open brine water tank valve.
(6) Loosen vent plug on top of backwash pump to prime pump.
(7) Turn BACKWASH VALVE handle downward to BACKWASH.
CAUTION
Do not hold START BACKWASH switch up for more than 5 seconds to avoid damage to the controls.
(8) Push BACKWASH switch up to START position and release immediately.
(9) When a steady stream of water flows from backwash pump vent plug, tighten vent plug.
NOTE
Solid-state timer will come on immediately. BACKWASH PUMP ON lamp will come on, pump will start
and backwash water will flow through the multimedia filter and out the waste water hose. The multimedia
filter gauge needle will move fully to right. During backwash, the backwash water flow rate varies
automatically from 0 to 70 to 120 gpm while washing and rinsing. Backwash operation is automatic and
lasts about 13 minutes
(10) When backwash is complete, BACKWASH PUMP ON lamp will go off and, pressure gauge and backwa h
s
flow gauge will return to "O". When backwash pump shuts off, turn BACKWASH valve handle upward to left to NORMAL
position. Close valve at brine water supply tank.
CAUTION
Since the multimedia filter uses brine water to backwash, it should not be drained or left inoperative
following backwash without first flushing with raw water for 5 minutes. Flush by operating filter normally.
(11) Start up the ROWPU after backwash in the normal manner (paragraph 2-9).
12-11. CITRIC ACID FEED.
After 20 hours of continuous operation, feed citric acid solution into filtered water in order to remove minor amounts of
scale which could accumulate during normal operation.
WARNING
Chemicals can cause sickness or even death if extreme care is not taken. Wear protective devices when
working with these solutions.
a. Using citric acid measure, put 0.75 pounds of citric acid in pail previously marked for CITRIC ACID.
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