Installation Instructions
Reverse Osmosis/Deionization Water System
Page 5
Maintenance
The RO/DI system contains filters and membranes which must
be replaced periodically for proper operation.
NOTE: Change-out frequencies may vary, depending on
feed water conditions.
The Reverse Osmosis/Deionization System has been tested
to ensure it will operate correctly. The following periodic
maintenance is recommended so the system will provide
years of trouble-free service:
To change filters and membranes follow these procedures:
1. Close feed water valve.
2. Open the product line and allow the system to
depressurize.
3. Loosen and remove filter housings using wrench provided
and discard cartridges and/or membrane.
4. Wash the inside of the housings using mild detergent and
soft cloth. Thoroughly rinse all soap before reassembly.
5. Replace filter cartridges and membrane (if necessary)
after sanitizing system.
Sanitizing instructions
To sanitize system follow these procedures with the feed
water valve closed and system de-pressurized.
1. Remove pre-filters and membrane from housings.
2. Use 5-1/4% unscented bleach such as Clorox or an
approved sanitizing solution.
3. Add one cap full (2 tsp. or 10 ml) of bleach to each pre
and post filter housing and membrane module.
4. Carefully re-fill housings with tap water and
temporarily replace
WITHOUT
carbon cartridge,
sediment cartridge, membrane or DI cartridge
installed.
5. Slowly open the feed water line and product water line
from the system.
6. Close the product line when water begins to come out
of the system and has a strong chlorine smell. The
system should shutoff when it pressurizes.
7. Let system stand for approximately 30-60 minutes.
8. After the minimum of 30 minutes perform the following
steps;
9. Open the product line and allow the system to flush until
the chlorine smell is gone.
10. Close feed water valve and leave the product line open.
11. Allow the system to de-pressurize.
12. Remove housings and empty the water.
13. Remove any protective wrap from pre-filters and
membrane and install them in the appropriate filter
housings. NOTE:
Be sure to check that the O-rings
are in place when installing cartridges in filter
housings.
Tighten the housings hand tight and the
sumps on the bottom can be tightened an additional
1/2-3/4 turn with supplied wrench.
14.
Slowly open feed water valve. When water begins to
drip from the product line, allow it to run until the
proper quality is being produced from the system.
(See System Startup)
Water quality
Water quality from an RO/DI system is normally determined
with a TDS Meter, Conductivity Meter or Resistivity Meter,
which measures total dissolved solids, conductivity or
resistivity of the water.
RO membranes are rated by the amount of dissolved solids
they reject expressed as “rejection percentage”.
Note: The membrane must be checked with a TDS meter.
Conductivity or Resistivity is not a good way to determine
membrane quality. Check the membrane at the DI
Cartridge Inlet Tubing.
For example:
If the feed water contains 100 ppm of dissolved solids and the
product water after the membrane (before the DI filter) tests at
10 ppm of dissolved solids the rejection rate is 90%. This
membrane efficiency must be checked on the inlet to the DI
cartridge to ensure the membrane is being checked and that
the DI cartridge isn’t giving a false reading. This is only for the
membrane performance and no the DI cartridge. The DI
cartridge should be checked using the meter that reflects the
specified water quality units.
The formula is as follows:
RO membranes should operate between an 80-97% rejection
rate. Once the rejection falls below 80%, the membrane must
be replaced.
Replacement part
Frequency
Pre-filter (sediment)
Every 6-12 months
Pre-filter (activated carbon)
Every 6-12 months
R/O membrane
Every 3-5 years
DI Cartridge
As needed
Percent Rejection
=
(Feed H
2
O TDS - Product H
2
O TDS) x 100%
Feed H
2
O