Owner Manual

Note: Stages 6 and/or 7 only exist on specific models.
Stage 1 – 3 Pre-Filters
Replace every 6 months or sooner if you notice a decrease in water flow or quality. The
replacement frequency depends on your water usage and source water quality. Changing the pre-
filters according to the schedule is essential to protect the RO membrane from chlorine and other
damaging contaminants.
How to change the stage 1 – 3 pre-filters:
1. Shut off the cold water supply and tank valve, and open the RO faucet to depressurize the
system. Place a bucket or towel under the system to catch any water spills.
2. If there is enough room under the sink and the filter system is hung on the wall, you can
twist the filter housing off without removing the system from the wall. Otherwise, you will
need to pull the system out, lay it down, and remove the housings at that point. Be careful
with the tubing connections when removing the system.
3. Twist off the filter housings in a counter-clockwise direction using the filter housing
wrench.
4. Refer to Installation Step 1.1 to install the new vertical filter cartridges, and tighten the filter
housings back on. Remember not to over tighten them, or they will be hard to unscrew next
time.
Stage 4 RO Membrane
Replace every 2-3 years or sooner if the TDS level starts increasing. Check the TDS level at least
once a month to monitor the system’s performance. The TDSrejection rate should be 90%+. To
calculate the rejection rate, divide the RO water TDS into your tap water TDS and subtract from 1.
For example, 20 (RO TDS) / 200 (Tap water TDS) = 0.1 1-0.1 = 0.9 so the TDS rejection rate
would be 90%. (NSF/ANSI STANDARD 58 for RO water filter).
Figure 17
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