The two methods to clean R.O. elements are citric acid for salt water and
surfactant for fresh water. The citric acid method is as follows:
- Adjust brine tank water level to 7 inches.
Ensure the soldiers
discharge any brine water at least 25 yards from raw water source intake.
Add one pound of citric acid to the brine tank.
- Disconnect backwash hose from backwash pump and connect vent vessels
hose to the backwash pump.
- Open regulate product flow valve, vent vessels valve and gate valve
on backwash tank.
- Remove product water hose from product tank and place it in a
designated waste area at least 25 yards from the raw water source intake.
Place brine hose in brine tank.
- Set element cleaning switch to start.
Brine flow gauge should
indicate 16 GPM or more.
Wait five minutes and check pH of water discharging into the brine
tank. Continue to add citric acid to the brine tank to adjust the pH near,
but not below 3.5.
- Allow solution to circulate for 45 minutes. Monitor temperature of
solution. If the temperature rises above 120 degrees, stop circulation.
- Set element cleaning switch to stop. Disconnect vent vessel's hose
from the panel, and place it in waste area.
Drain brine tank into waste
- Reconnect backwash hose and vent vessel's hose to the control panel.
Remove brine hose from brine tank and place it in waste area.
- Perform startup and operate ROWPU for ten minutes with the regulate
product flow valve fully open. Rinse backwash tank, pump and hose.
Adjust regulate product flow for mission flow.
Close vent product
- Operate for three minutes and check TDS, pH, and chlorine residual
of product water for standards.