Wall Mounted Commercial Reverse Osmosis Systems
Series PWR4011
PURE WATER
!
CAUTION: Please read the entire manual before proceed-
ing with the installation and startup. Your failure to follow any
attached instructions or operating parameters may lead to the
product’s failure, which can cause property damage and/or
personal injury.
• Do not use where the water is microbiologically unsafe.
• Pretreatment must be sufficient to eliminate chemicals that
would attack the membrane materials.
• Always turn off the unit, shut off the feed water, and disconnect the electrical power when working on the unit.
• Never allow the pump to run dry.
• Never start the pump with the reject valve closed.
• Never allow the unit to freeze or operate with a feed water
temperature above 100°F.
Save manual for future reference.
Please refer to Section 6 of this manual for operating parameters
according to your specific feed water Silt Density Index (SDI). For all
other settings according to your specific feed water quality, please
contact your Watts representative. A chemical analysis of the feed
water should be conducted prior to the initial sizing and selection of
this system.
Notes
Changes in operating variables are beyond the control of Watts. The
end user is responsible for the safe operation of this equipment.
The suitability of the product water for any specific application is the
responsibility of the end user.
Successful long-term performance of an RO system depends on
proper operation and maintenance of the system. This includes
the initial system startup and operational startups and shutdowns.
Prevention of fouling or scaling of the membranes is not only a matter of system design, but also a matter of proper operation. Record
keeping and data normalization are required in order to know the
actual system performance and to enable corrective measures when
necessary. Complete and accurate records are also required in case
of a system performance warranty claim.
Changes in the operating parameters of an RO system can be
caused by changes in the feed water or can be a sign of trouble.
Maintaining an operation and maintenance log is crucial in diagnosing and preventing system problems. For your reference, a typical log
sheet is included in this manual.
Do not use with water that is microbiologically unsafe or
Note:
of unknown quality without adequate disinfection before or after
the system.
I. Introduction
The separation of dissolved solids and water using RO membranes
is a pressure driven temperature dependent process. The membrane
material is designed to be as permeable to water as possible, while
maintaining the ability to reject dissolved solids.
The main system design parameters require the following:
• Internal flows across the membrane surface must be high enough
to prevent settling of fine suspended solids on the membrane
surface.
• The concentration of each dissolved ionic species must not exceed
the limits of solubility anywhere in the system.
• Pre-treatment must be sufficient to eliminate chemicals that would
attack the membrane materials.
A. Specifications
B. RO Overview
Reverse osmosis systems utilize semipermeable membrane elements to separate the feed water into two streams. The pressurized
feed water is separated into purified (product) water and concentrate
(reject) water. The impurities contained in the feed water are carried
to drain by the reject water.
RO Membrane
Feed WaterProduct Water
PWR40113012 PWR40113022 PWR40113032
Maximum Productivity
(gallons per day / gallons per
minute)
Maximum production based
on a feed water of 25°C, SDI
< 3, 1000 ppm TDS, and pH
8. Individual membrane productivity may vary (± 15%).
May be operated on other
feed waters with reduced
capacity.)
Quality (Typical Membrane
Percent Rejection)
Based on membrane manufactures specifications; overall system percent rejection
may be less.
Recovery (adjustable) 50 - 75 % 50 - 75 % 50 - 75 %
Membrane Size 4" x 40" 4" x 40" 4" x 40"
Number Of Membranes Per
Vessel
Pressure Vessel Array 11:11:1:1
Number Of Membranes 123
Prefilter (system ships with
one 5 micron cartridge)
Feed Water Connection 1" NPT1" NPT1" NPT
Product Water Connection 1/2" Tubing1/2" Tubing5/8" Tubing
Reject Water Connection 1/2" Tubing1/2" Tubing1/2" Tubing
Feed Water Required
The RO feed water must be pretreated in order to prevent membrane damage and/or fouling. Proper pretreatment is essential for
reliable operation of any RO system.
Pretreatment requirements vary depending on the nature of the feed
water. Pretreatment equipment is sold separately. The most common
forms of pretreatment are described below.
Media Filter - Used to remove large suspended solids (sediment)
from the feed water. Backwashing the media removes the trapped
particles. Backwash can be initiated by time or differential pressure.
Water Softener - Used to remove calcium and magnesium from
the feed water in order to prevent hardness scaling. The potential
for hardness scaling is predicted by the Langelier Saturation Index
(LSI). The LSI should be zero or negative throughout the unit unless
approved anti-scalents are used. Softening is the preferred method
of controlling hardness scale.
Carbon Filter - Used to remove chlorine and organics from the
feed water. Free chlorine will cause rapid irreversible damage to the
membranes.
The residual free chlorine present in most municipal water supplies
will damage the thin film composite structure of the membranes
used in this unit. Carbon filtration or sodium bisulfite injection should
be used to completely remove the free chlorine residual.
Chemical Injection - Typically used to feed anti-scalant, coagulant,
or bisulfite into the feed water or to adjust the feed water pH.
Prefilter Cartridge - Used to remove smaller suspended solids and
trap any particles that may be generated by the other pretreatment.
The cartridge(s) should be replaced when the pressure drop across
the housing increases 5 - 10 psig over the clean cartridge pressure
drop. The effect of suspended solids is measured by the silt density
index (SDI) test. An SDI of five (5) or less is specified by most membrane manufacturers and three (3) or less is recommended.
Iron & Manganese - Iron should be removed to less than 0.1 ppm.
Manganese should be removed to less than .05 ppm. Special media
filters and/or chemical treatment is commonly used.
pH - The pH is often lowered to reduce the scaling potential.
Silica: Reported on the analysis as SiO2. Silica forms a coating on
membrane surfaces when the concentration exceeds its solubility.
Additionally, the solubility is highly pH and temperature dependent.
Silica fouling can be prevented with chemical injection and/or reduction in recovery.
2
II. Controls, Indicators, and
Components
A. Controller - Controls the operation of the system.
B. Reject Control Valve - Controls the amount of reject flow.
C. Reject Recycle Control Valve – Controls the amount of recycle
flow.
D. Prefilter Pressure Gauges - Indicates the inlet and outlet pres-
sure of the prefilter. The difference between these two gauges is
the prefilter differential pressure.
E. Pump Discharge Pressure Gauge - Indicates the pump dis-
charge pressure.
F. Reject Flow Meter - Indicates the reject flow rate in gallons per
minute (gpm).
G. Product Flow Meter - Indicates the product flow rate in gallons
per minute (gpm).
H. Prefilter Housing - Contains the RO prefilter.
I. Automatic Inlet Valve - Opens when pump is on and closes
when the pump is off.
J. Low Pressure Switch - Sends a signal to the controller if the
pump suction pressure is low.
K. RO Feed Pump - Pressurizes the RO feed water.
L. RO Membrane Vessels - Contains the RO membranes.
(See Figure 1)
III. Operation
A. Installation
1. The water supply should be sufficient to provide a minimum of
20 psig pressure at the design feed flow.
2. Proper pretreatment must be determined and installed prior to
the RO system.
3. A fused high voltage disconnect switch located within 10 feet of
the unit is recommended. This disconnect is not provided with
the RO system.
4. Responsibility for meeting local electrical and plumbing codes
lies with the owner / operator.
5. Install indoors in an area protected from freezing. Space allowances for the removal of the membranes from the pressure
vessels should be provided.
B. Plumbing Connections
Note: It is the responsibility of the end user to ensure that the
installation is done according to local codes and regulations.
1. Connect the pretreated feed water line to the inlet valve (Figure #
1 item I). A feed water shutoff valve should be located within 10
feet of the system.
2. Temporarily connect the outlet of the product water flow meter
to drain. (Figure # 1 item G) The product water line should
never be restricted. Membrane and/or system damage may
occur if the product line is blocked.
3. Connect the outlet of the reject water flow meter to a drain.
(Figure # 1 item F) The reject drain line should never be restricted. Membrane and/or system damage may occur if the
reject drain line is blocked. An air gap must be located between
the end of the drain line and the drain. The use of a standpipe or
other open drain satisfies most state and local codes and allows
for visual inspection and sampling.
Figure 1
3
C. Electrical
Note: It is the responsibility of the end user to ensure that the
installation is done according to local codes and regulations.
1. Make sure the on/off switch located on the controller is in the off
position.
2. Wire the controller to a 230-volt single-phase breaker panel (see
figure 2).
PWR 4011 Controller
D. Startup
1. Verify that the pretreatment equipment is installed and working
properly. Verify that no free chlorine is present in the feed water.
2. Verify that the on/off switch is in the off position.
3. Install a 10" five micron filter cartridge in the prefilter housing.
(Figure #1 item H)
4. Open the reject control valve completely (Figure # 1 item B) by
turning it counterclockwise.
5. Close the reject recycle control valve completely by turning it
clockwise.
6. Open the feed water shutoff valve installed in step III-B-1 above.
7. Manually open the inlet solenoid valve (figure #1 item I) by turning the white lever located near the valve outlet.
8. Water will flow through the system and to drain through the
reject flow meter (figure # 1 item F).
9. Manually close the inlet solenoid valve after the air has been
purged from the system, or after 10 minutes, whichever occurs
first.
10. Open the reject recycle valve two turns.
11. Move the controller on/off switch to the on position.
12. Adjust the reject control valves (figure # 1 items B & C) until the
desired flows are achieved. Closing the reject valve increases
the product flow and decreases the reject flow. Opening the
reject recycle valve decreases both the reject and product flow.
See the flow rate guidelines and temperature correction table in
the appendix to determine the flow rates for different operating
temperatures.
13. Allow the product water to flow to drain for 30 minutes.
14. Turn off the system and connect the product line to the point of
use. (Figure # 1 item G) The product water line should never be
restricted. Membrane and/or system damage may occur if the
product line is blocked.
15. Restart the system and record the initial operating data using the
log sheet in the next section.
Figure 2
E. Controller
1. When the power switch is turned on the pump will run as long
as the circuit between the tank level terminals and the interlock
terminals are closed.
2. To install a tank level switch, remove the jumpers from the terminal strip and connect the level switch to the terminals. A small
plastic lever is installed in one of the terminals. This lever can be
moved to each terminal to open the contacts. The RO pump
and inlet valve will turn on when the level switch contacts are
closed (tank not full). The RO pump and inlet valve will turn off if
the level switch contacts open (tank full).
3. A pretreatment interlock switch can be installed in the same way
as the tank level switch.
4. If the pump suction pressure drops below the pressure switch
set point ( 5 – 8 psi) for five (5) seconds, the RO pump and
inlet valve will turn off. A red light on the front of the controller
will turn on to indicate that the unit has shutdown due to low
pressure. Turn the controller off and back on to reset the unit.
The controller is factory set to restart after a 20-minute delay.
The delay time can be changed by moving the jumper cap to
another position (see figure 2).
4
REMARKS
PRE FILTER
PRE FILTER
FEED WATER
FEED WATER
FEED WATER
OUTLET
PRESSURE
INLET
PRESSURE
CHLORINE LEVEL
HARDNESS
TEMP
PPM
PRODUCT TDS
PPM
FEED TDS
REJECT
PRESSURE
PRESSURE
DISCHARGE
DATEPRODUCT GPMREJECT GPMPUMP
F. Operation and Maintenance Log
Note: Change the prefilter when the differential pressure increases by 5 - 10 psi over the clean differential pressure.
Clean the RO membrane(s) when the product flow drops by 15% or more. (See appendix)
5
G. Troubleshooting
RO Troubleshooting Guide
SYMPTOMS
SALT PASSAGE PERMEATE FLOW PRESSURE DROP LOCATION POSSIBLE CAUSES VERIFICATION CORRECTIVE ACTION
Normal to increased Decreased Normal to increased Predominantly
first stage
Normal to increased Decreased Normal to increased Predominantly
first stage
Increased Decreased IncreasedPredominantly
last stage
Normal to moderate
increase
Decreased or
DecreasedNormal to moderate
increase
Can occur in any
stage
Decreased Normal All stages Organic foulingDestructive testing, e.g. IR
moderately
increased
Increased Increased Decreased Most severe in
the first stage
Increased Increased Decreased Most severe in
the first stage
Increased Normal to increased Decreased At random O-ring leaks, End or side
Increased Normal to low Decreased All stages Conversion too high.Check flows and pressures
Metal oxideAnalysis of metal ions in
cleaning solution.
Colloidal fouling SDI measurement of feed/
X-ray diffraction analysis of
cleaning sol. residue.
Scaling (CaSO
4, SiO2)
BaSO
4, CaSO3,
Analysis of metal ions in
cleaning sol. Check LSI of
reject. Calculate maximum
solubility for CaSO
2 in reject analysis.
SiO
4, BaSO4,
Biological foulingBacteria count in permeate
and reject. Slime in pipes
and vessels.
reflection analysis.
Chlorine oxidant attackChlorine analysis of feed.
Destructive element test.
Abrasion of membrane by
crystalline material
Microscopic solids analysis
of feed. Destructive element test.
Probe test. Vacuum test.
seal glue leaks.
Colloidal material passage.
against design guidelines
Improved pretreatment to remove metals. Cleaning with acid cleaners.
Optimize pretreatment system for
colloid removal. Clean with high pH,
anionic detergent formulation.
Increase acid addition and scale
inhibitor for CaSO
recovery. Clean with an acid formulation for CaCO
3, CaSO4 and BaSO4.
Shock dosage of sodium bisulfite.
Continuous feed of low conc. Of
bisulfite at reduced pH. Formaldehyde
sterilization. Clean with alkaline anionic
surfactant. Chlorine dosage up-stream
with subs. Dechlorination. Replace
cartridge filters.
Optimization of pretreatment system
(e.g. coagulation process.) Resin/
activated carbon treatment. Clean with
high pH detergent.
Check chlorine feed equipment and
dechlorination equipment.
Improved pretreatment. Check all filters
for media leakage.
Replace O-rings. Repair or replace
elements.
Reduce conversion rate. Calibrate
sensors. Increase analysis and data
collection.
3 and CaSO4. Reduce
Motor Troubleshooting Guide
PROBLEMPOSSIBLE CAUSECORRECTIVE ACTION
Motor fails to startBlown fusesReplace fuses with proper type and rating
Overload tripsCheck and rest overload in starter.
Improper power supplyCheck to see that power supplied agrees with motor nameplate and load factor.
Open circuit in winding or control switchIndicated by humming sound when switch is closed.
Mechanical failure
Short circuited statorIndicated by blown fuses. Motor must be rewound.
Poor stator coil connectionRemove end bells, locate with test lamp.
Rotor defectiveLook for broken bars or end ring.
Motor may be overloadedReduce load.
Motor StallsOne phase connectionCheck lines for open phase.
Wrong applicationChange type or size. Consult manufacturer.
Overload motorReduce load.
Low motor voltageSee that nameplate voltage is maintained. Check connection.
Open circuitFuses blown, check overload relay, stator and push buttons.
Motor runs and then dies downPower failureCheck for loose connections to line, to fuses and to control.
Motor does not come up
to speed
Not applied properlyConsult supplier for proper type.
Voltage too low at motor terminals because of line drop.
Broken rotor bars or loose rotor.
Motor takes too long to accelerate
Open primary circuitLocate fault with testing device and repair.
Excess loadingReduce load.
Poor circuitCheck for high resistance.
Defective squirrel cage rotorReplace with new rotor.
Applied voltage too lowGet power company to increase power tap.
6
Check to see if motor and drive turn freely. Check bearing and
lubrication.
Use higher voltage on transformer terminals or reduce load. Check connections.
Check conductors for proper size.
Look for cracks near the rings. A new rotor may be required as repairs are usually temporary.
Motor Troubleshooting Guide cont.
PROBLEMPOSSIBLE CAUSECORRECTIVE ACTION
Wrong rotationWrong sequence of phasesReverse connections at motor or at switchboard.
Motor overheats while running
under load
Motor vibrates after correcting
have been made
Unbalanced line current on
polyphase motors during normal
operation
Scraping noiseFan rubbing air shieldRemove interference.
Noisy operationAirgap not uniformCheck and correct bracket fits or bearing.
Hot bearings generalBent or sprung shaftStraighten or replace shaft.
Hot bearings ballInsufficient greaseMaintain proper quantity of grease in bearing.
These instructions do not cover all details or variations in equipment nor provide for every possible condition to be met in connection with installation, operation or maintenance. Chart courtesy of
Marathon Electric.
OverloadedReduce load.
Frame or bracket vents may be clogged with dirt and prevent proper
ventilation of motor.
Motor may have one phase openCheck to make sure that all leads are well connected.
Grounded couldLocate and repair.
Unbalanced terminal voltageCheck for faulty leads, connections and transformers.
motor misalignedRealign
Weak supportStrengthen base.
Coupling out of balanceBalance coupling.
Driven equipment unbalancedRebalance driven equipment.
Defective ball bearingReplace bearing.
Bearing not in lineLine properly.
Balancing weights shiftedRebalance motor.
Polyphase motor running single phaseCheck for open circuit.
Excessive end playAdjust bearing or add washer.
Unequal terminal voltsCheck leads and connections
Single phase operationCheck for open contacts
Fan striking insulationClear fan.
loose on bedplateTighten holding bolts.
Rotor unbalanceRebalance.
Excessive belt pullDecrease belt tension.
Pulleys too far awayMove pulley closer to motor bearing.
Pulley diameter too smallUse larger pulleys.
MisalignmentCorrect by realignment of drive.
Deterioration of grease, or lubricant contaminated
Excess lubricantReduce quantity of grease: bearing should not be more than ½ filled.
Overloaded bearingCheck alignment, side and end thrust.
Broken ball or rough racesReplace bearing: first clean housing thoroughly.
Open vent holes and check for a continuous stream of air from the motor.
Remove old grease, wash bearings thoroughly in kerosene and replace with new
grease.
RO System Troubleshooting
PROBLEMCORRECTIVE ACTION
General
High Product Water TDS
Membrane expanded.Replace membrane.
Membrane attack by chlorine Carbon pre-filter may be exhausted. Replace with a new cartridge.
Clogged pre-filter-creates pressure drop and low reject flow.Replace pre-filter cartridge.
Feed pressure too low.Feed pressure must be at least 20 psi.
Insufficiently flushed post-filter cartridge.Flush post-filter with pure water.
Brine seal on membrane leaks.Determine if seal or o-ring is bad. Replace as needed.
No Product Water or Not Enough Product Water
Feed water shut off.Turn on feed water.
Low feed pressure. Feed pressure must be at least 20 psi.Consider booster pump.
Pre-filter cartridge clogged.Replace pre-filter cartridge.
Membrane fouled.Determine and correct cause; replace membrane.
Product check valve stuck.Replace check valve fitting.
Low pump discharge pressureOpen pump discharge valve, replace pump
7
IV. Replacement Parts List
A list of common replacement parts is provided below. Contact your
dealer for replacement parts assistance.
ITEM NUMBER DESCRIPTION
1Pre filter housing 10" Big Blue
2RO Membrane Pressure Vessels 4" x 40" SS
3Pressure Gauge, 2", 0-100 psi, Dry
4Pressure Gauge, 2 1/2", 0-400 psi, LF
5Flow Meter 1-5 gpm
6Controller w/o contactor
7Pump power relay 24 VAC (pump/motor contactor)
8Pump & Motor 1 HP Single Phase (R14-01)
9Pump & Motor 1.5 HP Single Phase (R14-02 & 03)
10Low Pressure Switch, 6.5 psi
11Inlet Solenoid Valve, 1”, 24 volt coil
12Watts RO Membrane
13Filter Cartridge 5 micron 10” Big Blue
V. Membrane Replacement
1. Turn off the system and close the feed water shutoff valve.
2. Disconnect the membrane feed hoses by loosing the fittings between the end of the hoses and the pressure vessel end caps.
3. Remove the retaining "U" pins from the pressure vessels.
4. Push the old membrane out of the vessel in the direction of the
feed flow
5. Record the serial numbers of the new membranes.
6. Lightly lubricate the brine seals on the new membranes with
clean water.
7. Install the new membranes in the direction of flow with the brine
seal end going in last.
8. Lightly lubricate the end cap internal and external o-rings with
glycerin.
9. Install the end caps and secure them with the "U" pins.
10. Install the membrane feed hoses.
11. Verify that all retaining "U" pins are installed.
12. Follow the start up procedure in section III-D.
Flow Direction
Membrane
Brine
Seal
VI. Appendix
The following tables are intended as a guide to determining the flow
rates for the PWR4011 series RO systems. All flows are in gallons
per minute (GPM).
Nominal flows for systems with a feed water Silt Density Index
less than 3.
PWR40113012PWR40113022PWR40113032
Product1.252.53.75
Reject 1.252.53.75
Nominal flows for systems with a feed water Silt Density Index
of 3 to less than 5.
Multiply the nominal product flow at 25°C by the temperature correction factor to
determine the flow at various other temperatures.
LIMITED WARRANTY: Certain Watts Pure Water products come with a limited warranty from Watts Regulator Co. Other products may have no warranty or are covered by the original manufacturer’s
warranty only. For specific product warranty information, please visit www.watts.com or the published literature that comes with your product. Any remedies stated in such warranties are exclusive and
are the only remedies for breach of warranty. EXCEPT FOR THE APPLICABLE PRODUCT WARRANTY, IF ANY, WATTS MAKES NO OTHER WARRANTIES, EXPRESS OR IMPLIED. TO THE FULLEST EXTENT
PERMITTED BY APPLICABLE LAW, WATTS HEREBY SPECIFICALLY DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND IN NO EVENT SHALL WATTS BE LIABLE, IN CONTRACT, TORT, STRICT LIABILITY OR UNDER ANY OTHER LEGAL THEORY, FOR
INCIDENTAL, INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, LOST PROFITS OR PROPERTY DAMAGE, REGARDLESS OF WHETHER IT WAS INFORMED ABOUT
THE POSSIBILITY OF SUCH DAMAGES.