GE Merlin Manual

Merlin®
Reverse Osmosis System by GE
Installation and Maintenance Manual

2
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SAFETY GUIDES 3
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SAFETY GUIDES
Read and follow all steps and guides carefully before installing and using your
reverse osmosis system.
Do not use this product to make safe drinking water from non-potable water
sources. Do not use the system on microbiologically unsafe water, or water of
unknown quality without adequate disinfection before or after the system.
This reverse osmosis system contains replaceable components (membrane
elements). These components are critical for the effective reduction of total
dissolved solids and specific contaminants that are listed in the Product Data
Sheet.
The Merlin Reverse Osmosis System does not have a monitoring device for
contaminants. To verify that the system is performing satisfactorily the product
water should be tested periodically by the system’s installing dealer or a certified
laboratory, every six months. The laboratory should be certified for testing the
specific contaminants of concern. For a listing of certified laboratories, contact
local regulatory agencies. Within the United States, many state-run Department
of Natural Resources or Department of Health Services maintain listings of
certified laboratories.
Consult your local public works department for plumbing and sanitation codes.
Follow your local codes if they differ from this manual.
The reverse osmosis system works on water pressures of 40 psi
(2.8 bar) minimum to 80 psi (5.5 bar) maximum. Water pressure can be reduced by
installing a pressure reducing valve in the water supply pipe to the RO system. A
booster pump should be used for low pressure applications.
Do not install the reverse osmosis system in extreme hot or cold temperatures.
Temperature of the water supply to the reverse osmosis system must be between
40°F (4°C) and 100°F (38°C). Do not install on hot water lines.
The reverse osmosis membranes contain a foodgrade preservative for storage
and shipment. All new membranes require a minimum 2 hour rinse to properly
rinse out the preservative. The preservative is not harmful but makes the product
water taste objectionable. Rinsing the membrane also acts a a performance
conditioner. All new membranes will reach their stable maximum performance
after 8 hours of rinsing.

4 THE BASIC REVERSE OSMOSIS SYSTEM
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THE BASIC REVERSE OSMOSIS SYSTEM
Your Merlin Reverse Osmosis System is a water treatment unit. It uses water
pressure to reverse a natural physical process called osmosis. Water, under
pressure, is forced through a semi-permeable membrane to filter out minerals
and impurities. Treated drinking water goes to the faucet. Minerals and impurities
are sent to the drain with RO waste water.
The system includes replaceable filters and membrane elements. The prefilter
reduces sand, silt, dirt, rust particles, other sediments, and chlorine from the
water supply before they enter the RO membrane elements. The postfilter
reduces any tastes and/or odors that may remain in the water after passing
through the RO membrane elements.
BEFORE INSTALLING THE RO SYSTEM
• Best performance of the system will be achieved when the incoming water
has been treated (softened).
• The water coming into the system must be within certain limits for sediments,
pressure, etc. Refer to the specifications to determine if your installation is
within the limits.
• A water quality analysis can be performed to determine if incoming water
requires any treatment. Contact your dealer/installer.
• The filters and membrane elements in the RO system need to be replaced on
a regular basis. Follow the instructions for replacement that are in this
manual.
• The faucet options for the Merlin RO have not been tested or certified by the
Water Quality Association. It is recommended that faucets meeting National
Codes be used.
• The feed pressure gauge supplied with some Merlin RO systems has not been
tested or certified by the Water Quality Association. It is recommended to
remove the feed pressure gauge during normal system operation.
NOTE: For optimal system performance, use the system for at least
2 minutes continuously each day.
WARNING: The Merlin RO system is designed to work without the aid of
a pressurized storage tank. Installation of a pressurized storage tank will
negatively affect system performance.

THE BASIC REVERSE OSMOSIS SYSTEM 5
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MERLIN COMPONENTS
OnDemand RO
COMPLETE
MANIFOLD
PN 1244617 (1 pc)
SUPPORT
LEG
PN 1239708 (1 pc)
SUMP
& SEAL
SUMP
PN 1239705 (3 pcs)
O-RING
PN 1240326 (3 pcs)
ELEMENT
PN 4000569 (2 pcs)
FITTINGS
& LOCKING BAR
INSTALL KIT
PN 1255693
LOCKING BAR
DISCONNECT
PN 1239731 (1 pc)
COLLET
LOCK CLIP
RED
PN 1240626 (1 pc)
COLLET
LOCK CLIP
WHITE
PN 1240627 (5 pcs)
COLLET
LOCK CLIP
BLUE
PN 1240628 (2 pcs)
DRAIN
DISCONNECT
ELBOW - BLACK
PN 1264462 (1 pc)
STANDARD COMPONENTS SUPPLIED WITH
ALL MERLIN CONFIGURATIONS
TUBING
INSTALL KIT
PN 1255736
3/8" BLACK
TUBING (4 ft)
3/8" BLUE
TUBING (4 ft)
1/2" NATURAL
TUBING (4 ft)
1/2" RED
TUBING (3 ft)
SILICONE LUBRICANT
FEED
DISCONNECT
ELBOW - WHITE
PN 1240117 (1 pc)
PERMEATE
DISCONNECT
ELBOW - BLUE
PN 1240118 (1 pc)
FLUSH
DISCONNECT
ELBOW - LT BLUE
PN 1240119 (1 pc)
PLUG
1/4"
PN 1240624 (1 pc)
FAUCET
CONNECTION
FITTING
PN 1240625 (1 pc)
SILICONE
LUBRICANT
SGL USE TUBE
PN 1013501 (1 pc)
DRAIN BOA
KIT
PN 1240564 (1 pc)
AIR-GAP
FAUCET KIT
PN 3020487 (1 pc)
CARBON
PRE-FILTER
PN 3038333 (1 pc)
SEDIMENT
PRE-FILTER
PN 1266690 (1 pc)
CARBON
POST-FILTER
PN 255526-09 (1 pc)
Note: For use with
chlorinated water
supplies.
Note: For use with
non-chlorinated water
supplies.
ASO
CARTRIDGE
PN 1269491 (1 pc)
OnDemand RO
ADDITIONAL COMPONENTS
(see table below)
1255052 YES** Included - Included - Included Included
1263870 YES** Included - Included - Included -
3002041 NO - Included Included - Included Included
3002044 NO - Included Included - Included -
3002043 NO - Included - Included - -
MERLIN AGENCY CARBON SEDIMENT CARBON ASO DRAIN BOA AIR GAP
PN* CERTIFICATION PREFILTER PREFILTER POSTFILTER CARTRIDGE KIT FAUCET KIT
Merlin I
Merlin II
Sediment w/ faucet
Sediment w/o faucet
Light commercial
NAME
*Includes all "Standard" components.
**See Performance Data Sheet included with Merlin for Certification Information.
Note: For use
without a carbon
postfilter installed.
FEED PRESSURE
GAUGE
PN 3002791 (1 pc)

6 THE BASIC REVERSE OSMOSIS SYSTEM
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LOCATION OF SYSTEM
The reverse osmosis system is designed for installation under a sink, usually in
the kitchen or bathroom. The RO assembly can be placed on the cabinet floor in
any position that does not apply pressure on the disconnect elbows. The RO
product water faucet installs on the sink or on the countertop next to the sink.
The RO system can also be located in a location away from the faucet. A nearby
water source and drain point are required.
Water Supply: To provide supply water to the RO system inlet, a feed supply
fitting is required or install pipe fittings as needed. The feed water valve should be
located as close to the manifold assembly as possible. USE A POTABLE COLD
WATER SUPPLY ONLY. Softened water is preferred as it will extend the life of the RO
membrane element.
Drain Point: A suitable drain point is needed for reject water from the RO system.
A floor drain, laundry tub, standpipe, sump, etc. are all acceptable. If discharging
into the utility sink or standpipe, an air gap of greater than 1.5 inches above the
flood rim must be provided. A sink
p-trap drain adapter is included to install as an optional drain point where codes
permit.
Do not connect the system drain line to the dishwasher drain or near the garbage
disposal. Back pressure from these units may cause the air gap to overflow.
Dispensing Faucet: The faucet should be placed near the sink where drinking
water is normally obtained. Convenience of use (filling of water pitchers and
glasses) and an open area beneath the faucet under the sink for attaching
product and drain tubing are considerations. A 2-inch diameter flat surface is
required above and below the installation site. The thickness of mounting surface
should not exceed 1-1/4 inches. Avoid any strengthening webbing on the
underside of the sink.
NOTE: Keep the lengths of tubing short. Longer lengths of tubing will
decrease system performance. A booster pump can be used on the
supply line.
NOTE: All plumbing should be done in accordance with state and local
plumbing codes.
Some codes may require installation by a licensed plumber. Check with
the local plumbing authority prior to installation.
WARNING: All components and tubing should be located in an area
which is not exposed to freezing temperatures. Do not expose unit or
tubing to direct sunlight.

THE BASIC REVERSE OSMOSIS SYSTEM 7
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RO Manifold Assembly: The manifold can be installed on either the right or left
side of the under-sink area or cabinet. Installation in the basement is also an
option. One possible location is near the laundry/utility sink where cold potable
water and drain access are close. The location chosen should allow adequate
clearance and accessibility for membrane element changes.
Optional Flush Kit: The flush kit, if used, should be placed within 6 feet of the
manifold assembly. This will minimize pressure drop and allow the flush system to
operate most efficiently.
In restricted under-sink areas, it may be easier to install the faucet first. Allow
adequate tubing lengths for final system placement.
Figure 1 Typical Under-Sink Installation
Dispensing Faucet
with Air Gap
Inlet-1/2" Natural
Feed Water Valve
Cold Water Line Only
Carbon Postfilter
Waste Concentrate
3/8" Black
Drain - 1/2" Red
Product - 3/8" Blue
Drain Coupling
Install above P trap
Plugged Top Connector
Locking Bar
Keep to Minimum
Prefilter
RO Membranes
Support Leg (sump wrench)
Manifold
Elbow
Connectors
Note: If a flush tank is not
installed the manifold
connection must remain
plugged. Removal of plug
will cause a system leak.
Feed Pressure Gauge

8 THE BASIC REVERSE OSMOSIS SYSTEM
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Figure 2 Typical Basement Installation
Floor
Dispensing Faucet
without Air Gap
1.5" Air Gap Required
Inlet-1/2" Natural
Drain - 3/8" Black
Feed Water Valve
Cold Water Line Only
Carbon Postfilter
Product - 3/8" Blue
RO Assembly
Note: If a flush tank is not
installed the manifold
connection must remain
plugged. Removal of
plug will cause a system
leak.
Keep to Minimum

THE BASIC REVERSE OSMOSIS SYSTEM 9
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Figure 3 Typical Light Commercial Installation
1.5" Air Gap Required
Inlet-1/2" Natural
Drain - 3/8" Black
Feed Water Valve
Cold Water Line Only
Feed Pressure
Gauge
RO Assembly
Note: If a flush tank is not
installed the manifold
connection must remain
plugged. Removal of
plug will cause a system
leak.
External Prefilter
Product Storage Tank
To Point of Use
Vented to
Atmosphere
Liquid level float
sensor to control
feed solenoid valve
Feed Solenoid
Valve

10 THE BASIC REVERSE OSMOSIS SYSTEM
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REQUIRED TOOLS AND MATERIALS
• Adjustable wrench, and larger adjustable jaw pliers or pipe wrench to fit sink
drain
• Saw for cutting drain pipe
• Slotted and Phillips head screwdrivers
• Tubing cutters
• Electric drill and bits for cutting the faucet mounting hole
Note that some sinks will have a pre-drilled hole with a plug for the faucet.
INSTALLATION
STEP 1: Install cold water supply valve
STEP 2: Install drain adapter
STEP 3: Install faucet
STEP 4: Make tubing connections
STEP 5: Install RO assembly
STEP 6: Put system into operation
STEP 1: INSTALL COLD WATER SUPPLY VALVE
Comply with local plumbing codes. A typical connection using a water supply
valve is shown.
Water Supply Valve
Cold water pipes vary in size and style. The installer will determine type of valve
that will be used. Install a valve on the cold water supply pipe to adapt 1/2-inch
OD tubing. If threaded fittings are used, be sure to use pipe joint compound or
Teflon tape on outside threads.
Turn the valve off.
NOTE: Consult a licensed plumber if you are not familiar with plumbing
procedures.
NOTE: Be sure to turn off the water supply and open a low faucet to
drain the pipe.

THE BASIC REVERSE OSMOSIS SYSTEM 11
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STEP 2: INSTALL DRAIN ADAPTER
Follow the instructions in the Appendix for installation of the Drain Boa™, if
used.
The drain adapter is designed to fit 1-1/2-inch (3.8 cm) sink drain pipe.
The adapter installs directly to the sink tailpiece.
STEP 3: INSTALL FAUCET
A. Prepare Mounting Hole
1. Select a location for the faucet. Be sure it will fit flat against the sink or
counter and that there is space underneath for tubing.
2. If drilling is needed, make a 1-1/2 inch diameter hole. If the air gap module is
not being used, a smaller diameter hole is acceptable.
Figure 4
WARNING: To avoid damaging a sink, consult a qualified plumber or
installer for the proper method of drilling holes in porcelain or stainless
steel.
Air Gap Module Trim Ring
Standoff
Washer
Wing Nut
Water In Connection
Horseshoe
Clip
Gasket

12 THE BASIC REVERSE OSMOSIS SYSTEM
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B. Assemble Faucet
The tubing and fasteners are assembled to the faucet before the faucet is placed
in position. This can be done above the sink.
1. Slide the decorative ring over the tubing connections and up to the bottom of
the faucet.
2. Slide the gasket over the tubing connections and up to the bottom of the
faucet.
3. Slide the standoff onto the threaded tube, followed by the standard washer
and nut.
4. Screw the threaded hose connector on the end of the threaded tube.
5. Connect the blue 3/8-inch product tubing by firmly pushing it into the
connector.
6. If using the air gap module, push the black 3/8-inch tubing onto the small
hose barb. The red 1/2-inch tubing is pushed onto the large hose barb.
7. Put the faucet into position.
8. The horseshoe clip is positioned around the threaded pipe under the sink and
above the standoff. This clip should engage the tubing connected to the air
gap, if used.
9. Tighten the nut against the clip to hold the faucet in position.
STEP 4: MAKE TUBING CONNECTIONS
The connections to the faucet should be complete, the remaining connections
are:
• Feed connection―clear tubing from feed valve to white elbow connector
• Drain connection―either red tubing from the air gap or black tubing from
grey elbow connector will attach to the drain adapter
• Permeate connection―blue tubing from faucet to blue elbow connection
• To the flush tank (if used)
• Attach the fittings to the manifold
A typical connection is shown in Figure 5.

THE BASIC REVERSE OSMOSIS SYSTEM 13
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Figure 5 Side View and Cutaway of Tubing Fitting
Postfilter
Install the postfilter in line with the blue permeate tubing. Make sure flow direction
aligns with water path. Secure tubing with collet lock clips.
If the supplied postfilter is not used, install an ASO Cartridge in line with the blue
permeate tubing. The ASO Cartridge will help maintain proper mechanical
performance in the absence of the supplied postfilter. Contact your system
supplier for ASO Cartridge availability.
Drain Adapter (Optional)
The drain adapter has a rubber inlet that accepts the 3/8-inch black drain tube or
the 1/2-inch red tube. The 3/8-inch black tubing will connect here if the faucet is
not using the air gap module.
When the tubing is in position, use the supplied hose clamps to secure the
connection.
NOTE: Make sure the
tubing is pushed past the
O-rings for a secure fit.
Also, when replacing any
tubing, cut tubing back ~1/4
inch prior to re-inserting to
prevent leaks.
Tubing Collet O-Ring
O-Ring
Collet Lock Clip
NOTE: For optimal system performance, we recommend using tubing
lengths that are as short as possible.

14 THE BASIC REVERSE OSMOSIS SYSTEM
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Feed Pressure Gauge
The supplied pressure gauge can be connected to the feed line to monitor system
feed pressure. For proper system performance, the dynamic feed pressure must
be between 40 psi (2.76 bar) and 80 psi (5.52 bar) when the Merlin is in operation.
Flush Tank (Optional)
This kit will flush product water over the membranes following each use. The flush
kit extends membrane element life and reduces migration, or "creep" of ions to
the product water side of the membrane elements during periods of non-use. The
"creep" of ions across the membranes often causes lower rejection at system
start-up than the true capabilities of the RO system. Systems with flush kits
installed will maintain higher rejection levels following periods of inactivity.
To install the optional flush kit, remove the 1/4-inch plug and insert the
1/4-inch tubing into the top fitting on the RO assembly manifold. Be sure the
tubing is connected to the flush tank with an appropriate tank fitting. The empty
tank air precharge should be adjusted between 8 to 10 psi.
STEP 5: INSTALL RO ASSEMBLY
The RO Assembly includes the following components: sumps (3), support leg,
prefilter, RO membrane elements (2), and postfilter. The tubing is attached to the
manifold by the elbow connectors. When choosing a location for the system,
allow enough tubing for it to be moved for periodic servicing of the filters and
membrane elements.
NOTE: When sliding tubing into the drain adapter inlet, wet the tubing.
Water will help the tubing slide into the rubber inlet.
CAUTION: The feed pressure gauge is intended for use only during
installation and troubleshooting of the RO system. The pressure gauge
should be removed during normal system operation because some
some regulatory agencies did not evaluate the RO system with the feed
pressure gauge in place.
CAUTION: If the flush tank is not used, the 1/4-inch fitting on the
manifold must be plugged or water will leak out.

THE BASIC REVERSE OSMOSIS SYSTEM 15
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Figure 6 Merlin RO Assembly
Recommended Placement Positions
The Merlin assembly should be positioned in one of two ways.
The first position is with the unit standing upright using the support leg with the
sumps horizontal. The tubing is directed to provide the best fit.
The second position, sets the unit on end so the manifold is horizontal and the
sumps are pointing up. The tubing is directed upward and the locking bar is down
to lock the tubing connections.
See illustrations at left.
The table below shows the coding system for the fitting connections. Each fitting
has a unique “keyed” socket on the manifold. Each fitting also has a graphic
symbol molded into the elbow with a corresponding symbol on the manifold.
RO Membranes
Prefilter
Sumps
Support Leg
Manifold
Elbow
Connectors
WARNING: Do not attempt to mount/hang the Merlin. Do not try to drill
mounting holes anywhere on the system. If putting above
ground/cabinet level, a sturdy, permanent shelf is recommended.
First Position
Second Position
Locking Bar

16 THE BASIC REVERSE OSMOSIS SYSTEM
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When all of the connections have been made, use the locking bar to hold the
fittings in position. Match the symbols on the locking bar to the corresponding
symbols on the manifold.
Figure 7 Locking Bar
Connector Symbol Connection Tubing Color
OFlushing (optional) Blue
CFeed-Inlet Natural
UConcentrate Black
Product Blue
WARNING: Be sure to lubricate the O-rings on the fitting elbows with
silicone lubricant, prior to inserting into manifold.
WARNING: Do not turn the incoming water valve on until the locking
bar is in place.
NOTE: If the installation is not using the optional flush tank, the top
connection will not have tubing. Instead a plug will be inserted into the
fitting. Do not remove plug unless you are attaching the tubing and the
flush tank.
Symbols

THE BASIC REVERSE OSMOSIS SYSTEM 17
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STEP 6: SYSTEM STARTUP
1. Inspect all connections.
2. If the flush tank is not installed, the 1/4-inch port on the manifold must be
plugged.
3. Position manifold horizontal with openings facing up.
4. Remove new membrane elements from plastic packaging. The black and
yellow tapes surrounding the membrane are an important part of the
membrane element and should not be removed.
5. Lubricate element O-rings, brine seals, and sump O-rings with silicone
lubricant.
6. Securely insert O-ring end of membrane elements into manifold.
7. Remove prefilter from packaging. Check that gaskets are in place.
8. Place prefilter in manifold.
9. Replace sumps and tighten until it bottoms out.
Pressure Test System
To check for leaks, the system must be filled with water and brought up to
operating pressure.
1. Open cold water feed valve slowly. Run at 1/2 open for a minute, then open
fully.
2. Open faucet until water runs.
3. Check for leaks.
4. Purge the system. Open the faucet and run the water through the RO system
for two to eight hours.
The RO system is now ready for use.
CAUTION: Elements contain a foodgrade preservative. The use of
sterile/latex gloves is recommended.
NOTE: When the faucet is initially turned on, water may temporarily
sputter from the air gap until the air is purged. Allow 1 to 3 hours for any
trapped air noise in the system to subside.
NOTE: A minimum of 2 hour flush is required to remove the food grade
preservative. After 8 hours performance will reach its stable maximum
performance

18 TO CARE FOR THE RO SYSTEM
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TO CARE FOR THE RO SYSTEM
The components of the RO system are designed to function with minimal
maintenance. However, the membrane elements and filters will need to be
replaced on a regular schedule.
Run the system for at least two minutes each day for optimal performance.
REPLACEMENT OF PREFILTER AND POSTFILTER
The carbon/sediment prefilter reduces sediment and certain chemicals, such as
chlorine, from the water. Depending on water use and the amount of impurities,
this filter should be replaced every six to twelve months for residential
applications.
Whenever the prefilter is replaced, the postfilter should also be replaced.
Installations using more than 20 gallons product water per day should install
external filters (not supplied) to reduce chlorine and sediment larger than 10
microns.
REPLACEMENT OF RO MEMBRANE ELEMENTS
The functional life of the RO membrane elements will vary based on feed water
quality. Product water should be tested periodically to verify the membrane
elements are performing properly. For most residential applications, the RO
membrane elements should be replaced every two to four years.
REPLACEMENT OF THE PREFILTER, POSTFILTER, AND RO MEMBRANE ELEMENTS
1. Turn off the water supply to the RO System.
2. Reduce system water pressure by opening the faucet.
3. Disconnect locking bar and place the fittings (with tubing still connected) into
a tub or bucket.
4. Move system into a contained area, such as a sink or tub.
NOTE: Softened water is recommended for optimal system
performance and RO membrane element life.
CAUTION: Even with the water supply turned off the membrane and
prefilter sumps will contain a considerable amount of water. By
positioning the RO assembly in a sink or tub, most of the water will be
contained.

REPLACEMENT OF THE PREFILTER, POSTFILTER, AND RO MEMBRANE ELEMENTS 19
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5. Remove the support leg from the three sumps and unscrew the top sump as
shown to access the prefilter element. The support leg functions as a wrench
to loosen the sump, Figure 7.
Figure 8
6. Remove exhausted prefilter and discard.
7. If changing membrane elements:
A. Remove membrane sumps. Remove and discard used elements.
B. Remove new elements from packaging.
C. Lubricate element O-rings, brine seals, and sump O-rings with silicone
lubricant.
NOTE: There is no need to disconnect tubing from fittings on the
manifold. Remove locking bar and pull fittings out. Lubricate O-rings
with silicone prior to re-assembly.
NOTE: If changing only the prefilter and postfilter, the other sumps do
not need to be removed.
If changing the membrane elements, the prefilter and postfilter should
also be changed.
CAUTION: The person handling the filters and membrane elements
must have clean hands to keep the system sanitized. The use of sterile/
latex gloves is recommended.
CAUTION: Elements contain a foodgrade preservative. The use of
sterile/latex gloves is highly recommended.

20 REPLACEMENT OF THE PREFILTER, POSTFILTER, AND RO
MEMBRANE ELEMENTS
D. Securely insert O-ring end of elements into manifold. See
Figure 8.
E. Replace sumps and tighten until it bottoms out.
8. Sanitize the system.
A. The manifold should be positioned flat with the sump connections
facing up.
Figure 9
B. Pour a tablespoon (15 milliliters) of chlorine bleach into the center
opening of the prefilter sump connection. See Figure 9.
9. Install prefilter.
A. Remove new prefilter from packaging. Ensure gaskets are secure.
Insert prefilter into proper opening on manifold.
B. Lubricate sump O-ring with silicone lubricant.
C. With the prefilter element in place, screw the sump into the connection.
Tighten until it bottoms out.
10. Replace the postfilter.
A. To unlock the fittings from the tubing, push down on the collet sleeves
and pull the tubing out.
B. Discard the exhausted postfilter.
C. To prevent leaks, cut the tubing back approximately
1/4 inch prior to connecting the new postfilter. Make sure flow direction
arrow aligns with water path. Reinsert tubing and collect locks.
11. Re-connect the fittings to the manifold and lock in position with locking bar.
NOTE: The system should be sanitized whenever a membrane element
or filter is replaced.
Prefilter Center Opening Membrane Element Locations