
For Commercial Applications
ES-WQ-PWR4024
Job Name 
Job Location 
Engineer 
Approval 
 –––––––––––––––––––––––––––––––––––––––––––
 –––––––––––––––––––––––––––––––––––––––––
 –––––––––––––––––––––––––––––––––––––––––––––
 –––––––––––––––––––––––––––––––––––––––––––––
Series PWR4024
Commercial Reverse 
Osmosis Systems
Flow Rates: Up to 30 gpm (113 lpm)
Watts Pure Water Series PWR4024 reverse osmosis (RO) systems 
are commercial grade high-pressure RO units for the reduction 
of total dissolved solids from water. They are designed to supply 
reverse osmosis quality water with production rates ranging from 
20 to 30 gallons per minute. These units are designed for floor 
mount installations. Reverse osmosis is a process where highpressure feed water is fed into a semi-permeable membrane. In 
the membrane, pure water is allowed to pass through the membrane material and exit as purified permeate water. Dissolved 
mineral salts are not allowed to pass through the membrane and 
become a concentrated reject stream that is sent to a drain. These 
RO systems use high-pressure/high-rejection membranes to 
achieve a minimum average NaCl ionic rejection of 97 percent.
Watts Pure Water Series PWR4024 RO systems are a well 
designed, rugged line of purifiers. This series comes with a preselected assortment of features, including our digital controller for 
monitoring and operation. Corrosion resistant fiberglass reinforced 
plastic (FRP) membrane housings, inlet and outlet pre-filter pressure gauges, low-pressure switch with delayed auto restart, inputs 
for tank level and pretreatment interlock, conductivity meter, highconductivity alarm output, adjustable reject recycle, permeate and 
reject water flow meters, reject recycle flow meter, permeate water 
check valve, inlet diaphragm valve, membrane feed and reject 
water pressure gauges, auto flush, and adjustable reject valve, 
are all standard features. These systems are designed to feed an 
atmospheric storage tank for collection of the reverse osmosis 
water. Reverse osmosis water has a wide variety of applications 
including municipal water treatment, steam boiler and steam sterilizer make up, laboratory use, spot free rinsing, ice and beverage 
water, water for cooking, food processing, metal plating and finishing, as well as water for humidification. Reverse osmosis is also 
the pretreatment of choice for ion exchange type de-ionization (DI) 
systems. Using RO water as make up to a DI system reduces the 
exhaustion rate of the DI resin by up to 95 percent saving time, 
money, and chemicals associated with DI resin regeneration.
  Contractor 
  Approval 
  Contractor’s P.O. No. 
  Representative 
 ––––––––––––––––––––––––––––––––––––––––––––
 –––––––––––––––––––––––––––––––––––––––––––––
 ––––––––––––––––––––––––––––––––––
 ––––––––––––––––––––––––––––––––––––––––
PURE WATER
Series PWR4024
Features
• Powder coated carbon steel support frame
• Corrosion resistant 300psi FRP high-pressure membrane housings
• Pressure gauges for pre-filter inlet/outlet, membrane feed, and 
reject water pressure
• Low feed water pressure safety switch
• Digital microprocessor based controller with delayed auto restart 
after low pressure shut down
• Permeate water conductivity meter with high conductivity alarm 
output
• Tank level and pretreatment interlock inputs
• High-pressure/high-rejection membranes with 97% minimum 
average salt rejection
• Permeate, reject recycle, and reject water flow meters
• Adjustable reject and reject recycle valves
• Permeate check valve
• Automatic inlet diaphragm valve
• 90 gallon per minute high flow 316 stainless steel pre-filter
Note: Do not use with water that is microbiologically unsafe or of 
unknown quality without adequate disinfection before or after the 
system. 
Watts product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements, 
please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials without prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.
Standards
Pre-filter Housing- NSF/ANSI Certified Std. 42 
Membrane Housings- NSF/ANSI Certified Std. 61

Specifications
Watts Pure Water Series PWR4024 reverse osmosis system shall 
be installed to provide reverse osmosis quality water. The RO 
system shall be installed after a Series PWS water softener so that 
scale forming calcium and magnesium hardness cannot scale the 
RO membrane. Series PWC backwashing carbon filter shall be 
installed on the RO feed water line to remove chlorine and prevent 
membrane degradation due to chlorine attack. Series PWM backwashing sediment filter shall also be installed on the RO feed water 
line to reduce the silt density index of the water to prevent particulate fouling of the RO membrane.
The RO system shall be a high-pressure/high-rejection type unit 
complete with permeate and reject water flow meters, reject recycle water flow meter, pre-filter inlet and outlet pressure gauges, 
membrane feed and reject water pressure gauges, FRP membrane housings, automatic inlet diaphragm valve, low feed water 
pressure switch, reject and recycle valves, digital controller with 
conductivity meter and high-conductivity alarm output, storage 
tank level and pretreatment interlock inputs, 10 horse power multistage centrifugal high-pressure pump, and all other components 
necessary for proper operation. The system shall be a floor mount 
design. The RO permeate water shall be collected in an atmospheric storage tank with the tank level controlled by an electronic 
level float. The RO shall be equipped with inputs for the tank level 
float as well as pretreatment interlock to shut the RO system down 
in the event the pretreatment begins a backwash cycle. Electrical 
requirements are 230 volt 60 hertz three phase. A local drain is 
required to accept drain water from the system. The feed water 
pressure must not fall below 20psi. The feed water temperature 
must not fall below 35°F or exceed 100°F (2-39°C).
The system shall produce reverse osmosis quality water with 97 
percent minimum average ionic rejection of total dissolved solids 
when operated within the manufacturer’s operational specifications.
Dimensions - Weights
C
FRONT
B
Feed Water Guidelines
pH  ...................... 6 to 9
Hardness (maximum) ....... Less than 1 grain per gallon as
   CaCO3 (Softened) or anti scale 
   chemical injection if not softened 
   (contact your Watts representative)
Feed Water Pressure (minimum) .20psi 
Temperature ............... 35 - 100°F (2 - 38°C)
Free Chlorine (maximum) ..... None Allowed
Iron (maximum) ............. Less than .1mg/L
Oil and H2S  ............... None Allowed
Turbidity  ................. Less than 1.0 NTU
Silt Density Index ........... Less than 5.0 SDI 
Notes:
* For all other guideline information please contact your Watts representative.
* Published maximum production rates are based on a feed water of 77°F, SDI 
of less than 3, 1000 ppm TDS, and pH 8. Individual membrane productivity may 
vary (± 15%). May be operated on other feed waters with reduced capacity.
* Percent rejection is based on membrane manufacturer’s specifications; overall 
system percent rejection may be less.
Performance
Maximum Productivity (gallons per minute) 20 25 30
Quality (typical membrane percent rejection) 98%
Recovery (adjustable) 65% – 75%
Membrane Size 4" x 40"
Membrane Array (four elements per vessel) 2:2 3:2 4:2
Prefilter 
(system ships with five micron cartridges)
Feed Water Connection 2" Flange
Product Water Connection 1.5" Flange
Reject Water Connection 1" Flange
Feed Water Required (GPM at 65% recovery) 31 39 46
Minimum Feed Water Pressure  20 psig
Drain Required (maximum) 31 39 46
Electrical Requirement 
(other voltages available)
Motor Horse Power / Type 10 / TEFC
Dimensions L x W x H (approximate) 192" x 26" x 72"
Shipping Weight (estimated pounds) 1400 1600 1800
7 round x 20" 
230 VAC, 3-phase, 
60 Hz, 30 amps
Ordering Information
Model No. Description
A
SIDE
 MODEL NO.  DIMENSIONS  WEIGHTS
  A B C
     in. mm in. mm in. mm lbs kgs
 PWR40243163 26 660 74 1880 186 4724 1400 636 
 PWR40243203 26 660 74 1880 186 4724 1600 727 
 PWR40243243 26 660 74 1880 186 4724 1800 818
A Watts Water Technologies Company
ES-WQ-PWR4024  1122    © 2011 Watts
PWR40243163 20 GPM Reverse Osmosis System with Micro Processor 
Controller and Auto Flush
PWR40243203 25 GPM Reverse Osmosis System with Micro Processor 
Controller and Auto Flush
PWR40243243 30 GPM Reverse Osmosis System with Micro Processor 
Controller and Auto Flush
USA: North Andover, MA • Tel. (800) 224-1299 • www.watts.com 
Canada: Burlington, ON • Tel. (888) 208-8927 • www.wattscanada.ca