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9
Membrane Replacement
This reverse osmosis system contains a replaceable component (the
RO membrane) which is critical to the efficiency of the system.
Replacement of this reverse osmosis membrane should be with one
of identical specifications as defined by Watts to assure the same
efficiency and contaminant reduction performance.
Membranes have a life expectancy between 2 and 5 years, de-
pending on the incoming water conditions and the amount the
RO system is used . This reverse osmosis membrane is critical for
effective reduction of total dissolved solids (TDS) . The product water
should be tested periodically to verify that the system is performing
satisfactorily .
Normally, a membrane would be replaced during a semiannual or
annual filter change . However, if at any time, you notice a reduction
in water production or an unpleasant taste in the reverse osmosis
water, it could be time to replace the membrane . Watts recommends
replacing the membrane when TDS reduction falls below 75% .
Note: A water sample may be sent to Watts for a free diagno-
sis of your membrane performance. To send a water sample,
use two (2) clean containers and fill ½ cup of tap water in one
container and ½ cup of reverse osmosis water in 2nd container.
Clearly label each sample. Send the samples to the address
listed on the cover of this manual attention “Water Samples”.
Watts will test the water and mail or call you with the results.
Step A –
Turn off the incoming water
supply to the RO by turning
the knob on the Adapt-A-
Valve™ clockwise until it
stops .
Step B –
Open the RO Faucet and
allow water to drain from
the tank until it is completely
empty .
Removing the Membrane
Step A –
Use a
5
⁄
8
" wrench to remove the Green Tube fitting on the
left side of the horizontal membrane housing (end with one
elbow) .
Step B –
Remove the cap from the membrane housing by turning it
counterclockwise to loosen .
Note: A double sided wrench may
be purchased from Watts to aid with
loosening the cap / filter housings.
Step C –
Remove membrane housing
from the holding clips . Using
a pair of pliers, grip the PVC
tube of the RO membrane and
pull firmly on the membrane to
remove from the housing and
discard .
Installing the Membrane
Step A –
Lubricate the O-rings on the new membrane with a water
soluble lubricant such as KY Jelly ®. Insert the end with the
two black O-rings first into the
housing .
Step B –
Once membrane has been
inserted into the housing you
must take your thumbs and
give a firm push to properly
seat the membrane . Replace
membrane housing cap and
tighten .
Step C –
After replacing membrane
housing into clips, attach the
green tube to the elbow on
cap using
5
⁄
8
" wrench .
Step D –
Follow the Start Up Instruc-
tions on Page 7 .
Procedure for Extended Non-Use
(More than 2 months)
Turn off the water supply by turning the knob on the Adapt-A-
Valve™ clockwise until it stops, and open the RO faucet to empty
the storage tank . (Save a few ounces of RO water) . Once the
storage tank is empty, remove the membrane, and place it in a
sealed plastic bag with the RO water saved earlier and store in your
refrigerator .
For restart, reinstall membrane (See Page 9 for membrane installa-
tion procedure) and follow startup procedure on Page 7 .