Changing Filters, Cont. 17. Open the tank valve to allow the shutoff valve to open and resume normal operation of the RO. If the
permeate pump does not begin to cycle, lift up on the black handle of the dispensing spigot and let the
water run until the permeate pump begins to cycle.
18. Turn on the storage tank ball valve.
19. Inspect for leaks.
Note: With a new installation or after replacing the primary filter with the storage tank empty, it is normal for the
water to run steady to the drain. The pump will start to cycle once the pressure starts to build in the storage
tank. It may take up to 20 minutes for the permeate pump to cycle, which is normal.
Changing the Carbon Pre-Filter
1. Turn off the ball valve on top of the storage tank 1/4 turn clockwise (See Figure 2).
2. Turn off the feed water supply valve.
3. Lift the black handle of the dispensing spigot and wait at least five minutes for the pressure to be
relieved from the system.
4. Remove the Carbon Pre-Filter housing by turning it counterclockwise (as viewed from the bottom) and
dispose of the spent cartridge. If you encounter difficulty, use the filter wrench provided with your RO.
5. Wash out the filter housing using warm soapy water and rinse thoroughly.
6. Be sure the O-Ring is properly seated in the groove located in the top of the filter housing and
lubricated with glycerin.
7. Sanitize the appliance. See Sanitizing the WaterMax RO Appliance.
8. Insert the new Carbon Pre-Filter of the same type and reattach the filter housing.
9. Follow steps 11–19 of Changing the Sediment Pre-Filter.
Changing the Dual-Function Pre-Filter
Follow the instructions in Changing the Sediment Pre-Filter. Ensure that air is purged from the filter for any
appliance equipped with a permeate pump.
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