Pura QCRO4V-50 User manual

Quick Change Reverse Osmosis Drinking Water System
Installation, Operation & Service Instructions with Part List
Model No. QCRO4V-50
www.pura.com
This system certified by WQA
according to NSF/ANSI 58 for
TDS reduction, as verified and
substantiated by test data.

Safe Practices
Throughout this manual there are paragraphs set off by special headings.
NOTE: Note is used to emphasize installation, operation or maintenance information which is important, but does not
present any hazard. Example:
NOTE: The nipple must extend no more than 1 inch above the cover plate.
Caution!: Caution is used when failure to follow directions could result in damage to equipment or property. Example:
CAUTION! Disassembly while under water pressure can result in flooding.
WARNING!: Warning is used to indicate a hazard which could cause injury or death if ignored. Example:
WARNING! Electrical shock hazard! Unplug the unit before removing the timer mechanism or cover plates!
Serial Number
The serial number is located on the rear of the R.O. manifold housing. Record this number on the warranty page located
at the end of this manual.
NOTE: Do not remove or destroy the serial number. It must be referenced on requests for warranty repair or replacement.
This publication is based on information available when approved for printing. Continuing design refinement could cause
changes that may not be included in this publication.
WARNING! If incorrectly installed, operated or maintained, this product can cause severe injury. Those who
install, operate, or maintain this product should be trained in its proper use, warned of its dangers, and should
read the entire manual before attempting to install, operate or maintain this product.
Attention PURA Customer:
This system is intended for use on potable water supplies or disinfected water containing cysts. Do not use where water
is microbiologically unsafe or with water of unknown quality. If bacterial contamination is present, a recognized method
of water disinfection is required.
Check with your public works department for applicable local plumbing and sanitation codes. Follow your local codes if
they differ from the standards used in this manual.
For installations in Massachusetts: Massachusetts Plumbing Code 248 CMR shall be adhered to. Consult your licensed
plumber for installation of this system. The use of saddle valves is not permitted in Massachusetts.
The PURA Quick Change Drinking Water System contains a replaceable reverse osmosis membrane filter which is critical
for the effective reduction of Total Dissolved Solids. The filtered water should be tested periodically to verify that the
system is performing properly.
Serial Number Label
R - MM-DD-YY-XXXXXX
Date of
manufacture
Serial
Code
Data
Plate
Label Containing
Model #

1
Table of Contents Page
Specifications and Performance Data Sheet .................................................................. 2
Suggested Installation Equipment ............................................................................ 4
Overview of the PURA Quick Change RO System’s Components ................................................. 5
Package Contents......................................................................................... 6
Preparation............................................................................................... 7
Installation
Step 1 Select Component Installation Locations ............................................................10
Step 2 Faucet Installation................................................................................11
Step 3 Install Adapter Valve on Water Supply ..............................................................14
Step 4 Connect System Drain ............................................................................14
Step 5 Install Reservoir Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Step 6 Install Filter System Assembly .......................................................................16
Step 7 Start Up .........................................................................................17
Performance and Technical Information ......................................................................18
Installing an RO to Service Other Water Using Appliances .......................................................19
Service and Maintenance ..................................................................................20
Sanitation Procedure.......................................................................................20
Parts Breakdown ..........................................................................................21
Troubleshooting ...........................................................................................23
Warranty Information.......................................................................................25
Quick Change Reverse Osmosis Drinking Water System
Installation, Operation & Service Instructions with Part List

2
Specifications and Performance Data Sheet
Model # Part # Stage 1 Stage 2 Stage 3 Stage 4 Storage Tank Faucet
QCRO4V-50 940465 Sediment Filter Activated Carbon
Filter
Reverse Osmosis
Membrane
Activated Carbon
Filter
Metal Tank -
3.2 Gallons Chrome - AirGap
Daily Production Rate*
L/day (G/day) . . . . . . . . . . . . . . . 76.8 (20.3)
Efficiency Rating**% . . . . . . . . . . 12%
Recovery Rating*** . . . . . . . . . . . 21%
Average Reduction**** %. . . . . . 85%
Typical System Flow Sequence . Sediment Filter Activated Carbon Prefilter Reverse Osmosis Membrane 
Storage Tank Activated Carbon Postfilter Dispensing Faucet
Sediment Filter (Stage 1). . . . . . . 5 Micron
Activated Carbon Prefilter
& Postfilter (Stage 2&4) . . . . . . . . Carbon Block 5 Micron
Reverse Osmosis Membrane
(Stage 3) . . . . . . . . . . . . . . . . . . . . Thin Film Composite
Production Rate1. . . . . . . . . . . . . QCRO4V-50 36.5 gpd (138 L/day)
Ratio of Product to Flush Flow2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard Applications 1:3 - 1:5
Storage Capacity
. . . . . . . . . . . . . . . . . . . . . . . . . . . . Metal – Capacity 3.2 Gallon (12 Liters)
13.7"
13.7"
Product Water Storage Tank
15.8”
2.0”
4.7”
14.3”
2.5”
13.1”
This system certified by WQA
according to NSF/ANSI 58 for
TDS reduction, as verified and
substantiated by test data.
1 Rating at 50 psi, 77°F, 750 mg/L TDS influent, without storage tank.
2 May vary with pressure.
* The daily production rate is the volume of product water produced by the system per day and is determined by testing in accordance with the procedure outlined in NSF/ANSI Standard 58.
** System’s Efficiency rating as verified by testing in accordance with NSF/ANSI standard 58. Efficiency rating means the percentage of the influent water to the system that is available to the user as reverse
osmosis treated water under operating conditions that approximate typical daily usage.
*** System’s Recovery rating as verified by testing in accordance with NSF/ANSI Standard 58. System’s Recovery rating means the percentage of the influent water to the membrane portion of the system that is
available to the user as reverse osmosis treated water when the system is operated without a storage tank or when the storage tank is bypassed.
**** Minimum TDS reduction per NSF/ANSI 58 is 187 mg/L. Influent TDS is 750 mg/L.
Dimensions

3
NOTES
1. A booster is strongly recommended to improve the reduction of
TDS. Higher pressures will help maintain the membrane’s maximum
rejection performance.
2. The reverse osmosis membrane used in these systems may be
damaged by chlorine. These systems include activated carbon filters
which protect the membranes by reducing chlorine. Influent chlorine
should not exceed 3 mg/L.
3. A softener is strongly recommended for water over 10 gpg hard.
Installing a system without a softener on water with hardness higher
than 10 gpg will reduce the life of the membrane.
4. Additional information on factors that affect RO performance can be
found in the “Performance & Technical Information” section.
Table 1
Recommended Influent Water Characteristic
Pressure 40 - 100 psi
Temperature 40 - 77 ºF
Total Dissolved Solids (TDS)10 - 2500 ppm (0 - 2500 mg/L)
pH 5 - 10
Chlorine20 - 3 ppm (0 - 3 mg/L)
Chloramine 0 - 3 ppm (0 - 3 mg/L)
Turbidity 0 - 10 NTU
Hardness30 - 10 gpg
Iron 0 - 1 ppm (0 - 1 mg/L)
Bacterial Quality Potable
Filter Cartridge Specifications
Part # Purpose
Micron
Rating Capacity Flow Rate
Working
Temperature
Range
Working
Pressure Range
Rated
Life* STAGE
Sediment Filter 41407001 Sediment Reduction 5 2000 gallons
(7570 liters)
0.5 gal/min
(1.9 liters/min)
4-38° C
(40-100° F)
207-689 kPa
(30-100 psi) 6 Months 1
Carbon Block
Filter 41407002 Chlorine Taste and Odor 5 2000 gallons (7570 liters)
0.5 gal/min
(1.9 liters/min)
4-38° C
(40-100° F)
207-689 kPa
(30-100 psi) 6 Months 2 & 4
Part # Purpose
Recovery
(Product
Water/ Inlet
Water)
TDS
Reduction* Rating** Flow Rate
Working
Temperature
Range
Working
Pressure
Range (1) Rated Life* STAGE
RO Membrane
50 GPD 41407003 TDS Reduction 21% 85%
50 gallons/day
(189 liters/day)
(No Storage
Tank Attached)
0.5 gal/
min (1.9
liters/min)
4-38° C
(40-100° F)
50-120 psi
(345-828 kPa)
36
Months 3
* The performance and life of a reverse osmosis membrane or filter element is highly dependent upon pressure, temperature and dissolved solids (TDS).
** Manufacturer’s Specification only with inlet conditions of 345 kPa (50 psig), 25° C (77° F), going to atmosphere. The actual volume of product water and rejection percentage will vary with differences from the
test conditions that membrane ratings are based upon.
(1) Pressure Regulator is recommended for feed water pressures exceeding 552 kPa (80 psig).
Performance Data Sheet
Contaminant Reduction Table: Model QCRO4V-50
This system has been tested according to WQA S-300 for reduction of the substances listed below. The concentration
of the indicated substances in water entering the system was reduced to a concentration less than or equal to the
permissible limit for water leaving the system, as specified in NSF/ANSI 58.
Substance Allowable Influent
Challenge Concentra-
tion (mg/L)
Average Actual Influent
Concentration (mg/L)
Maximum Permissible
product water concen-
tration (mg/L)
Average Actual Effluent
Concentration (mg/L)
Actual Minimum
Percent Reduction
Average Actual Per-
cent Reduction
TDS 750 ± 20% 778 187 116 84.5 85.1

4
Suggested Installation Equipment
Recommended Tools
1. Utility Knife
2. Flathead Screwdriver
3. Phillips Screwdriver
4. Center Punch
5. 7/8” Stepped Drill Bit
6. Finish Hole Saw
7. Porcelain Saw
8. 1/8” & 3/8” Drill Bits
9. Heavy Duty Drill
10. Work Light
11. 2 Adjustable Wrenches
12. Pressure Gauge
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11
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2
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5
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6
7
8
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4
Figure 1

5
Overview of the PURA Quick Change RO System’s Components
Manifold Assembly
The manifold assembly serves as the functional hub of the PURA system by
directing the flow through each of the system’s main components.
Sediment Filter
The sediment filter screens out particulate material, such as dirt, sand, or rust,
which may clog the other filters in the system.
Activated Carbon Filter
The activated carbon prefilter reduces chlorine which may damage the RO
membrane filter. The activated carbon postfilter serves as a final polishing
step to improve the water quality. They must be regularly checked and/or
replaced to prevent premature membrane failure and poor water quality.
Reverse Osmosis Membrane
The RO membrane (4) reduces dissolved substances and other microscopic
impurities. It consists of a membrane envelope wound around a perforated
tube. Product water diffuses through the membrane to the inside of the
envelope where it flows to and is collected by the tube. Impurities are flushed
away in the drain stream.
The RO membrane featured in the PURA system offers exceptional
contaminant rejection, application versatility, and long life. The membrane
material is sensitive to an attack by chlorine. The activated carbon filter must
be maintained properly to prevent premature failure of the RO membrane.
For long term storage the RO membrane should be refrigerated to maximize
performance once used. DO NOT ALLOW TO FREEZE.
NOTE: This preservative must be flushed from membrane before use. If
ingested it may cause irritation of the gastrointestinal tract, colic, diarrhea,
or other similar symptoms. The manufacturer recommends discarding all
the product water for at least one hour of operation before drinking or
use in food preparations. WaterGroup highly recommends discarding the
product water for a full 24 hours to flush the preservative and to properly
hydrate the membrane for maximum performance.
Drain Line Flow Control
The flow control assembly or concentrate flow control (5) regulates the flow rate of the flushing (drain) stream and to
maintain pressure in the RO membrane filter.
Automatic Shutoff
The automatic shutoff (6) automatically stops the flow of water through the PURA system when the storage tank is full.
Storage Tank
The storage tank (7) collects and stores the water produced by the RO system. A compressed air diaphragm drives the
water to the polishing filter and faucet. The ball valve (11) provides a convenient way to lock water in the tank during
transport and filter changes.
Dispenser Faucet
The PURA faucet (8) allows the product water to be drawn from the system with a simple rotation of the handle. This air
gap style faucet prevents the unit from siphoning drain water back into the system. It features a built-in siphon break
for concentrate discharge as required by most plumbing codes.
NOTE: Cleanliness is essential in the Preparation procedure. Be sure to wash your hands thoroughly before handling
filters. The use of surgical gloves is strongly recommended.
Figure 2

6
Carton 2 Carton 3
2X
3X
1. RO Manifold with Flow Control
2. Sediment Filter
3. Carbon Block Filter
4. RO Membrane
5. Carbon Block Filter
6. Storage Tank
7. Tank Base (Optional)
8. Faucet and Hardware
9. Drain Saddle
10. Tank Shut-off Valve
11. Adapter Valve ASVPP5 (3/8” or 1/2”)
12. 2X Locking Clip (3/8”)
13. 2X 3/8” Elbow
14. Faucet Adapter
15. Locking Clip (1/4”)
16. 1/4” Elbow
17. 4X #10 Phillips Self Tapping Screws
18. Teflon Tape
19. 1/4” Tubing (4 ft. White;
4 ft. Orange)
20. 3/8” Tubing (4 ft. White;
4 ft. Orange;
4 ft. Blue)
21. Installation Template Sheet 11X17
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15
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17
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20
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21
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19
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16
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18
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11
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10
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1
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2
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5
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7
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Figure 3
Main Carton
Package Contents

7
Tubing Connectors
The PURA system features reliable and convenient push-to-connect tubing connectors. Tubing is easily connected and
disconnected from these fittings as follows.
Connect:
Cut the tubing squarely with a sharp knife. Be careful not to crush the tubing. To
avoid leaks, make sure the tubing end is smooth and free of burrs and abrasions.
Lubricate the end of the tube with water or a light coat of silicone and push
the tube end firmly into the fitting. You should feel it push past the O-ring. Avoid
bending the tubing sharply away from the fitting.
Disconnect:
Hold the collar against the fitting body and pull the tube from the fitting.
In the unlikely event that the connection leaks, remove and recut the tubing.
Check the inside of the fitting for debris or O-ring damage. Reconnect.
Push-to-connect tubing connectors grip the outside diameter of the tube. To
help assure a reliable connection, it is important to use high quality tubing with a
consistent outside diameter.
Quick-Connect Fitting
Insertion & Removal of Plastic or
Copper Tubing
1. Simply
push in
tube to
attach.
2. Tube is secured in position. 3. Push in collet from both sides to
release tubing.
Preparation
Figure 4
1. Cut tube squarely with a sharp knife.
This manual covers the technical aspects of PURA Quick Change drinking water systems. It is important to read this manual
thoroughly so that you can properly apply, install, and service these systems.
The substances reduced by this system are not necessarily in the customer’s untreated water.
Warranty
A limited warranty is extended to the original end user from WaterGroup. This warranty is printed on the back cover of the
Owner’s Guide.
Application Guidelines
The PURA system is designed for use on potable water supplies meeting the guidelines outlined in Table 1. The system
should be installed on a home’s cold water line. The flushing stream should discharge through an approved siphon break.
Installation of this system must comply with state and local laws and regulations.
Package Content
The PURA system is shipped from the factory in carton:
NOTE: The filter elements are shipped in their own sealed packaging. This will help to simplify preparation of the system
and to maximize the shelf life of the RO membrane element.
Product Information

8
Verify Flow Control Location
The RO manifold comes attached with the elbow fitting flow control. This
flow control is attached to the manifold by quick disconnect fitting which
allows it to be easily changed. Verify it is properly located in the outlet next
to the
symbol.
Storage Tank Preparation
NOTE: Changing the air pressure will alter the amount of water stored in the tank. Increasing the pressure will decrease
capacity while decreasing pressure will increase capacity.
Check Air Pressure
Using a tire gauge with 1 psi increments, check the air pressure in the empty storage tank. The air pressure should be
between 6 and 8 psi. Depending on the influent water pressure the air pressure may need to be adjusted. To modify the
air pressure use a bicycle-type hand pump to increase the air pressure or depress the stem of the air valve to decrease
the pressure.
Install Tank Shut-off Valve
WARNING! Do not use the tank ball valve to lift or carry the tank.
Flow Restrictor
1. Apply teflon (PTFE) tape to threaded
fitting at top of tank. Wrap tape
around clockwise 3 to 6 times for a
good seal.
2. Attach shut off valve. 3. Connect white 3/8” tubing to tank.
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1
2
3
Figure 6
Figure 5
3/8” White Tubing

9
Figure 7
The exact placement of the components will vary by installation. Although shown beneath a sink, it may be installed
in a basement, crawl space, or in an adjacent cabinet. Regardless of where the system is installed, the flow sequence
described by (figure 7) must be observed.
The PURA drinking water system is designed to be mounted near a sink for easy access to cold water and drain lines.
Lengths of 1/4-inch and 3/8-inch OD plastic tubing will be required to make this installation.
Evaluate the installation site to determine the easiest path for the plumbing to follow. Take care to make the installation as
neat as possible.
NOTE: Install the 3/8” orange drain line from the air gap faucet to the drain adapter so that it runs downward with no
loops or low spots. Otherwise the unit will overflow at the air gap siphon break built into the faucet, or make
irritating gurgling sounds.
Installation
Pura Faucet
3/8” White Tubing
RO Manifold
1/4” Feed Line (White)
Pressure Tank
Cold Water Supply
3/8” Product
Water Line (Blue)
3/8” Tank
Line (White)
Drain
Connection
1/4” Drain Line to Air Gap (Orange)
3/8” Drain Line
from Air Gap (Orange)
The additional Point of use connection
(Icemakers etc) can be tapped from
here with the use of reducing Quick
Connect Tee (14” X 3/8” X 3/8”)
(Part # PP30121208W).
STEP 2
STEP 3
STEP 4
STEP 5
STEP 6

10
The following steps will enable you to install the system quickly and orderly. Some variation may be necessary depending
on the installation. See page 4 for a check list of tools and materials.
Typical installations follow this sequence:
1. Select Component Installation Locations
2. Faucet Installation
3. Install Adapter Valve on Water Supply
4. Connect System Drain
5. Install Reservoir Tank
6. Install Filter System Assembly
7. Start-Up
Step 1 – Select Component Installation Locations
• Dispenser Faucet – The faucet is designed to be mounted on the rear lip of the sink. It may be installed in an existing
sprayer attachment hole or in a hole drilled at the time of installation. It may also be mounted to an adjacent counter
top. It should be positioned so that water is dispensed over the sink. A 7/8” diameter hole is required.
• Important considerations:
• Access to the bottom (undersink) of the faucet is required for attachment of product water line.
• There should be no undersink obstructions which would prevent smooth tubing runs to the drain connection, or RO
module assembly.
• Filter System Assembly – The filter system assembly is designed to be mounted on any rigid vertical surface such as a
cabinet sidewall, sheetrock in exposed stud. It should be positioned such that there is access to an inlet water source
and drain. The installation should also allow convenient access for servicing.
• Inlet Water Supply Connection – Once a location is chosen for installation of the filter system assembly, select a nearby
cold water line to provide the water source for the system.
NOTE: Follow all local plumbing codes when connecting to service water.
• The Reservoir Tank – Position the reservoir tank near the faucet for optimum convenience. The reservoir tank will weigh
about 28 pounds (13 kg) when full of water, so it must be positioned on a stand.
The reservoir operates best in the vertical position, but it will operate on its side.
• Drain Connection – The most convenient entry to the drain is directly above the P-trap of the kitchen sink. However,
the drain water from the system can be connected to adjacent sinks or a floor drain. Extra care should be taken when
entering drains near dishwashers or food waste disposals as back flow may occur through the air gap and cause
flooding.
NOTE: Follow all local plumbing codes when connecting to drain.

11
Step 2 – Faucet Installation
To simplify its access and installation, we suggest you install the faucet on the rear lip of the sink. It should be evenly
positioned with the sink faucet and spray attachment. Should the spray faucet hole not be available for the installation,
the sink must be drilled.
NOTE: It is recommended retaining the services of a professional counter top craft person when a hole is needed in
granite or other specialty counter top materials.
Sink Drilling Instructions
Stainless Steel Sink
Porcelain Enamel Sink
Follow these basic guidelines when drilling a porcelain sink:
One proven tool is the Relton porcelain cutter kit when used with a slow speed drill (300-400 rpm).
• Drill a pilot hole through the porcelain and base material with the carbide tip drill.
• Build a putty dam around the drill area. Add enough water to lubricate cutters and reduce cutting noise.
• Insert the porcelain cutter into the drill. Place the drill tip in the pilot hole. Check for free movement.
• Apply light pressure to the cutter tool and start the drill motor at low speed (300-400 rpm). When the initial cut has
been made in the porcelain, speed may be increased. After a complete ring has been cut through the porcelain,
change over to the metal cutter. Avoid contacting the outer rim of cut porcelain when drilling.
CAUTION! Avoid high drill speed during penetration of porcelain. A single speed drill can be used at a slow
speed by switching it on and off quickly.
• Use a slow speed and light pressure to cut away the porcelain.
• Stop when you reach the metal under the porcelain. Remove the cutter and clean the porcelain chips from the
surface. Continue cutting through the metal.
NOTE: Ceramic tile counters should be treated like porcelain when penetrating the surface, then treated as metal to
complete the hole with carbide drills. Formica countertops can be drilled with a high-speed wood drill.
Pilot Drill Spring Loaded Porcelain Saw Finish Hole Saw
Penetrate the porcelain to the base
material.
Protect the surrounding porcelain
material.
Use the appropriate tool to drill the
base material.
1. Select and mark the
proper faucet location.
2. Center punch hole to
provide a starting point
for your drill.
3. Drill a 7/8” hole in the sink using a stepped 7/8” drill
bit. If no stepped bit is available, start by drilling
a 1/4” hole. Using this hole as a starting point
progressively drill larger holes. Increase drill size by
1/8” until you reach a 7/8” hole.

12
1/4” Orange
Tubing
3/8” Orange
Tubing
Faucet
Base
Split Washer
Drain Line from Faucet
(3/8” Orange Tubing)
Drain Line from RO Manifold
(1/4” Orange Tubing)
Product Line from RO Manifold
(3/8” Blue Tubing)
Faucet Adapter
Nut
Lock Washer
Flat Washer
Spacer
(Optional)
O-ring (in base)
Figure 10
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9
Faucet Adapter
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1
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2
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5
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6
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7
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8
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3
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4
NOTE: The spacer is required for stainless steel sinks and thin counter tops. If sink is being
installed on a thick (5/8” or thicker) counter the spacer is not required.

13
Verify faucet body, metal base, and rubber base washer are in place above sink (Items 1, 3, and 2).
Lower faucet into mounting hole and place faucet over hole.
Install slotted washer, spacer, faucet washer, and nut onto faucet nipple below sink and snug them up
(Items 4, 5, 6, 7 and 8). Be sure to properly align faucet before tightening. Do not over tighten.
Install faucet connector (Item 9), packaged with faucet, onto faucet nipple.
The spacer is typically necessary on stainless steel sinks and thin counter tops. If counter top or sink is too think (5/8” or
thicker) remove the spacer from the installation.
CAUTION! Plastic Parts will break if screws are over tightened!
Tubing Connections
1. At the bottom of the faucet assembly you will find three tubing connections;
2 are barbed and one is a push in
type fitting.
2. For the Air gap you will use the 2 barb fittings, the smaller fitting is for the 1/4”
tubing and will be connected to the RO system. The larger barb fitting will
use the 3/8” tubing and will be connected to the drain.
NOTE: If you have difficulty fitting the tubing onto the barbed fittings, try
running hot water over the end of the tubes.
NOTE: Cut the tubing to be longer than what you will need because you
will be able to trim it after you install the faucet assembly. Prepare
the tubing with a fresh cut and make sure that it is free of dirt and
any foreign materials.
3. Take another length of 3/8” tubing and make sure it is has a fresh cut and is
free of foreign materials and any scratches on the outside surface. Install the
tubing into the push in type fitting at the base of the faucet. Make certain
that it is inserted all the way in; once inserted give it a slight pull to make sure
it is locked into the fitting. You have now completed the tubing connections.
NOTE: To disconnect tubing from the product water fitting, hold the
collet firmly against fitting body and pull the tube from the fitting.
Repeated assembly and disassembly will cause wear to the inner
body. Visually inspect for excessive wear and replace the inner
body as needed to protect against any leaks.
Cleaning the Faucet
Wipe the faucet with a soft cloth, avoid abrasive cleansers.
Faucet Assembly
1/4”
Orange
Tubing
3/8”
Orange
Tubing
Product Line from
RO Manifold
(3/8” Blue Tubing)
Faucet Adapter
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9

14
Step 3 – Install Adapter Valve on Water Supply
1. Shut off water at supply valve.
Before installing the adapter valve onto the supply line, in-
stall the adapter as needed. The conversion adapter can
be threaded to either side of the valve to allow the valve
to fit both 1/2” and 3/8” supply lines.
Adapter
1/2” Configuration 3/8” Configuration
or
Verify the gasket is
properly seated
Cold
Water
Line
to Faucet
Cold Water Supply
Valve
4. Connect riser hose to adapter valve. 5. Insert tubing into quick connect
fitting on valve.
6. Open the cold water supply valve
and check for leaks.
2. Disconnect hose from supply valve. 3. Install adapter valve on supply valve.
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3
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4
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1
Step 4 – Connect System Drain
Plumbing codes require that the drain from reverse osmosis drinking water systems be discharged through an air gap
siphon break. The faucet incorporates an air gap into its body. The discharge from the air gap must be connected to the
plumbing system for proper drainage. This connection can usually be made beneath the sink. Incorrect installation may
result in overflow of the air gap or excessive noise. If the concentrate water is discharged to an open drain, the air gap
may not be necessary.
The air gap feature of the faucet requires standard 3/8” tubing.
Connections to undersink plumbing can be made with a saddle clamp designed to accept the drain tubing from the
faucet. Drain Saddle Kit is supplied for 1-1/2” undersink drain plumbing (Figure 14). Be sure to check and follow local
plumbing codes prior to installation.
NOTE: For installation in Massachusetts, Plumbing Code 248 CMR shall be adhered to. Consult your licensed plumber for
installation of this system. The use of saddle valves is not permitted in Massachusetts.
CAUTION! The Adapter valve should be connected to cold water supply only. Connection to hot water
supply will damage the system and will void all warranty

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4
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1
Many homes are equipped with disposals and dishwashers. Special care must be taken when these appliances are
present to prevent improper air gap performance. Home drain plumbing must be free of any blockage since this may
cause a backup of dishwasher and disposal waste into the air gap outlet tube and result in improper air gap performance.
To perform a simple drain check, fill the sink basin with several inches of water, pull the plug, and observe the drainage. If
water backs up into the second sink (if present), or if drainage is slow or there is excessive gurgling, drain blockage may be
present.
Undersink drain plumbing usually resembles one of the following descriptions. In all cases, the drain tubing from the air gap
(RO outlet) should run downward, free of dips and loops. The air gap outlet must not be connected to the effluent side of
the trap. This can vent sewer gas, which will produce foul odors.
Single basin sink without disposal
• Connect the RO outlet to the tailpiece directly beneath the sink.
• If a dishwasher drain connection is present, the RO outlet must be connected above it.
Single basin sink with disposal
• Connect the RO outlet to the dishwasher drain port on the disposal if available.
• If the dishwasher drain port is not available, other arrangements
must be made such as running the RO outlet to a basement sump.
• Do not connect the RO outlet to the plumbing below the disposal.
Double basin sink with disposal, single trap
• The fitting which joins the drains from the disposal and second
sink should be directional. If not, then we recommend that it be
replaced.
• Connect the RO outlet to the tailpiece just below the second sink.
• If a dishwasher drain is present and cannot be relocated, the RO
outlet must be connected above it.
• Do not connect the RO outlet to the horizontal plumbing between
the two sink drains.
Double basin sink with disposal, double trap
• Connect the RO outlet to the tailpiece just below the second sink.
• If a dishwasher drain is present and cannot be relocated, the RO
outlet must be connected above it.
Step 5 – Install Reservoir Tank
Place the reservoir tank in the location previously selected. The stand included with the reservoir is optional. It may be
installed with or without the stand.
Figure 14
1. Install the drain saddle
valve on to the drain pipe.
See figure 7 on page 9 for
its location.
2. Tighten the clamps with
the help of the two bolts.
3. Drill 3/8” hole through one
side of the pipe. The drill
should be kept straight
and centered to avoid
damaging the saddle
valve. Do not drill through
both sides of the pipe!
4. Attach 3/8” orange tube by
slipping the tube through
the black compression nut
and hand tighten the nut
on to the saddle valve.
CAUTION: The drill should be
kept straight and centered to
avoid damaging the saddle
valve.
WARNING! Do not
overtighten.
WARNING! Do not
drill through both
sides of pipe!.
Sink
Disposal
Do not
install here
Install here
Drain Line from
Air Gap (Air
Gap Only)
Sink

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Step 6 – Install Filter System Assembly
The mounting bracket contains four mounting slots. The holes are sized to accept #10 round head wood screws (supplied).
Some types of surfaces such as particle board or drywall, may require the use of plastic screw anchors or toggle bolts to
provide adequate support for the unit.
1. Tape the paper template included with this unit to the wall with the base of the template on the bottom of the cabinet
(or higher). Be sure to leave adequate space (8 1/2” or more from the centerline) on both sides of the template.
2. Drill 1/8” hole at each location as indicated on the template.
3. Remove template. Thread one of the included wood screws into each hole leaving approximately a 1/2” space
between the screw head and mounting surface.
4. Hang the bracket on the mounting screws. If unit is loose, tighten the screws further.
Install Filter Cartridges
1. Twist the cartridge to lock it into the manifold. (as shown)
Connect System
When cutting plastic tubing, use a sharp utility knife. Cut the tubing squarely. See page 7 for cutting and connecting tubing.
2. Connect 1/4-inch OD white plastic
tubing from the feed water supply
source to the system inlet on the
manifold.
1. Connect quick connect elbows
to the three open connection
locations on the unit. Firmly push
the fittings into place, then pull
back lightly to lock them in.
3. Connect 3/8-inch OD blue plastic
tubing from the product water
faucet to the manifold.

3

2
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1
White Blue
Stage 1
Sediment Filter
Stage 2
Carbon Block
Filter
Stage 3
Reverse Osmo-
sis Membrane
Stage 4
Carbon Block
Filter
Figure 15
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2 3
4
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1
12"

17
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4
4. Connect the 1/4” OD orange
tubing from the air gap inlet of the
faucet to the concentrate outlet
on the RO manifold.
Orange
Step 7 – Start-Up
1. Sanitize the storage tank (see page 20 for sanitization procedure).
2. Check system to verify all components are correctly installed
3. Open inlet valve and tank valve.
4. Check system thoroughly for leaks. If any are found, shut off both inlet and tank valves and correct the issue.
5. Allow system to run & fill tank for 1-2 hours. You will hear the water running to drain while the unit is running. Once the
water stops running to drain the tank is full.
6. Open faucet to flush carbon fines & sanitization solution. Once the flow begins to slow down (around 20 minutes after
opening) turn off the faucet.
7. Allow the tank to fill completely again.
8. Once full, open the faucet and allow the water to run for 24 hours to break-in the RO membrane and completely flush
the system. This will allow your system to run at optimal efficiency.
9. Close faucet and allow tank to fill.
10. System is ready to use
NOTE: It is normal if the air gap faucet makes gurgling noises and drips small amounts of water during start-up
procedure. This should subside once start-up procedure is complete.
WARNING! Do not drink water produced by the system until the start-up procedure has been
followed completely!
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5
6
5. Connect the 3/8” OD white
product water tube from the tank
to the manifold.
6. Attach locking clips to each white
elbow fitting. Do not attach one to
the blue flow control. Clips should
slide in behind collet on the fittings.

18
The performance of the PURA system can be characterized and judged by the quality and quantity of the water
produced by the system. By measuring the contaminant removal performance and flow rates of the system, its operating
status can be easily evaluated.
Factors Which Affect Performance
Performance of the reverse osmosis membrane is affected by several factors which must be considered when judging the
condition of the system. The main factors which affect system performance are pressure, temperature, total dissolved solids
level, recovery and pH.
Pressure
Water pressure affects both the quantity and quality of the water produced by the RO membrane. Generally, the
more water pressure, the better the performance of the system. Be careful not to go below 40 psi or exceed 100 psi, the
minimum and maximum operating pressure of the system.
Temperature
The reverse osmosis process slows with decreasing temperature. To compensate, a temperature correction factor is
used to adjust the actual performance of the RO membrane filter to the standard temperature of 77°F (25°C). This allows
the performance of the unit to be accurately gauged against published standards. Temperature does not affect the
concentrate flow rate.
Total Dissolved Solids
The minimum driving force which is necessary to stop or reverse the natural osmosis process is termed osmotic pressure. As
the total dissolved solids level of the feed water increases, the amount of osmotic pressure increases and acts as back
pressure against the reverse osmosis process. Osmotic pressure becomes significant at TDS levels above 500 mg/L (ppm).
Hardness
Hardness is the most common membrane foulant. If ignored, this relatively harmless component of feed water will scale
a membrane over time. Use of a softener will reduce the fouling effect on a membrane. One way to detect too much
hardness in the feed water is the weight of a membrane installed for a period of time. A fouled membrane (dried) will
weigh significantly more than a new membrane. The increase in weight is a result of precipitated hardness inside the
membrane.
Iron
Iron is another common membrane foulant. There are a variety of types of iron, some of which cannot be removed by
an iron filter. Clear water iron can be removed more effectively by a softener. Particulate iron can be removed more
effectively by a 1 micron filter. Organic-bound iron can be removed only by activated carbon or macroporous anion
resin. If there is enough iron to exceed the EPA secondary drinking water standard and softening the water is not an
option and the iron is soluble, then an iron filter is appropriate. If none of these are an option then regular replacement of
membranes will have to be accepted.
NOTE: Increased weight of the RO cartridge may be a foulant other than hardness.
Product Water Recovery
Product water recovery plays an important role in determining membrane and system performance. Recovery refers to
the amount of water produced in relation to the amount of water sent to drain. The standard calculation is:
% Recovery = Product Water ÷ (Product Water + Waste Water) x 100
The system uses a flow control assembly to restrict the flow of waste water to the drain. This restriction helps maintain
pressure against the membrane. The sizing of the flow control assembly determines the recovery rating of the system. The
system is manufactured with a recovery rating designed to be around 25%. Depending on temperature, pressure and
tolerances the actual recovery value may be slightly different for each system.
Performance Measurements
When collecting water samples from the manifold, insert a short 2”-3” length of tubing into the fitting on the manifold to
catch the water sample.
TDS can be measured with an electronic TDS meter. PN 66760
Performance & Technical Information