US Water Systems Defender 223-DFROM Series, Owner'S Manual

Page: 21 / 33

21
75% Recovery System Adjustment
Turn the concentrate valve clockwise until the permeate flow rate and the concentrate flow rate are at designed
standards. Turn the recycle valve until the recycle flow rate is at the desired rate. If necessary, adjust the
pump throttle valve, concentrate valve and concentrate recycle valve until the proper flow rates are achieved.
Not exceeding 150 PSI pump pressure and not reducing the pump pressure below 80 PSI . The concentrate
recycle flow rate and the concentrate flow rate must equate to the minimum flux rate or higher in high flow
feeds or damage to the membrane may occur.
Once the flow rates have been adjusted, monitor the system over the first two weeks and make fine adjust-
ments to maintain the proper flow rates. When there is a change in the feed water TDS level or temperature,
the flow rates may need to be re - adjusted. The recycle flow rate can be determined using the desired Recov-
ery Rate (75% maximum) and the Permeate Flow Rate. The equation is as follows;
RO System GPD Rating / 1440 mins (mins in a day) = Permeate Flow Rate GPM
Permeate Flow GPM / 75% (0.75) = Total Flow GPM
Total Flow GPM - Permeate Flow Rate GPM = Concentrate Flow GPM
Minimum Flux Rate (determined by membrane size/diameter) GPM - Concentrate Flow Rate GPM = Recycle
Flow Rate GPM
4.0” Membrane Minimum Flux Rate = 3.0 GPM
Example;
2000 GPD System
2000 GPD / 1440 Mins = 1.39 GPM Permeate Flow
1.39 / 0.75 = 1.85 GPM Total Flow
1.85 GPM - 1.39 GPM = 0.46 GPM Concentrate Flow
1 (min 2.5” Membrane Flux) - 0.46 GPM = 2.54 GPM Recycle Flow
Once the adjustments are made the system is operational.
IMPORTANT!
Be sure to flush the storage tank as the initial water the RO makes during adjust-
ment is not up to quality. This can usually be done by letting the tank fill for about
50 gallons and emptying the tank twice or directing the permeate water to a drain
until the water quality stabilizes.
RO Start - up
Operating DO ’ s and DON ’ Ts
DO:
•
Change the cartridge filters regularly
•
Monitor the system and keep a daily log
•
Run the system, as much as possible, on a con-
tinuous basis
•
Adjust the system recovery to the recommended
value
•
Always feed the pump with filtered water.
DON ’ T
•
Permit chlorine to enter or be present in the feed
water.
•
Shut down the system for extended periods
•
Close the throttle valve completely.
•
Operate the system with insufficient feed flow
•
Operate the pump dry.
CAUTION: EXCESSIVE RECYCLING MAY CAUSE PREMATURE FOULING OR SCALING OF THE MEM-
BRANE ELEMENTS.