About the Reverse Osmosis Membrane
When used under operating conditions specified on page 1 of
the manual, your reverse osmosis membrane should last at
least one year. You should replace the membrane after 18 to 24
months. Replace it sooner if you notice a return of unpleasant
tastes or odors or a noticeable decline in water production. The
precise life span of your system's membrane will depend on
the quality of the water entering the system and the frequency
with which you use it. Frequent system use prevents the
filtered salts and minerals from building up on the membrane
as scale. The more water the system is required to produce,
the longer the membrane will last. You may wish to find a
variety of uses for your system in order to prolong the life of the
membrane.
NOTE:
If system stands for more than 2 to 3 days without being
used, the storage tank should be emptied.
Replacing the Membrane and Filters
NOTE:
When installing a new GRO membrane element and flow
control, it is recommended that you replace the pre-
filter and post-filter cartridges as well.
1. Turn off the cold water supply. Allow five minutes for
system to depressurize.
Place a tray under the system to catch any water that spills
during removal of the filter housings.
2.
Open drinking water faucet to drain tank. When tank is
drained, close faucet.
3. Disconnect the tubing connections from the GRO element.
Install the new GRO element, permeate checkvalve, and
capillary reject flow controller.
4. Unscrew filter housings from caps and discard used
cartridges.
5. Remove black rubber O-rings from grooves in housings.
Wipe grooves and O rings clean.To replace the filters, see
Replacing the Pre-Filters and Post-Filter on page 9.
6. Lubricate O-rings with a coating of clean silicone grease.
With two fingers, press each O-ring securely into groove
below the threads of the appropriate housing.
CAUTION:
The rubber O-ring provides the water-tight seal
between the cap and the bottom of the housing. It is
important that the O-ring be properly seated in the
groove below the threads of the housing or a water
leak could occur.
NOTE:
After installing new GRO element, flow control, and
cartridges, allow system to run for 3 hours to fill tank.
Check for leaks every hour. As pressure builds in
tank, leaks may occur that did not exist directly after
installation. When the RO element and cartridges have
been changed, follow the system start-up procedure in
Step 11: System Start-up.
REPLACING THE 3RD STAGE REVERSE OSMOSIS MEMBRANE
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Installation and Operation Manual
