Sanitizing the WaterMax® RO Appliance Sanitize the RO assembly and storage tank during installation and when replacing filters to prevent bad taste
and odor in the drinking water. Common household chlorine bleach (5.25% - unscented) is suitable for this
purpose.
Hint: Before you sanitize an RO appliance that has been in operation in a customer’s home, the customer may
wish to draw off some drinking water into a pitcher. It may be several hours until a sanitized RO appliance has
generated sufficient clean water to meet their needs. Also, disconnect the icemaker to prevent it from freezing
up, as well as any similar devices.
Caution: The procedures described below are for maintenance purposes only and are not intended to sterilize
an appliance that has become heavily contaminated from misuse or neglect.
Sanitize the RO Assembly
1. Close the feed water valve and open the RO spigot to drain any water from the storage tank. The tank
should be light when picked up. If the tank is heavy, leave the spigot open and use a tire pump (See
Installation Tool List) to pump air into the tank to displace the water. When the tank is drained, use a
low-pressure tire gauge to adjust the air charge to between 5 and 7 psig.
2. Close the RO spigot.
3. Remove the pre-filter housing(s) and discard the spent cartridge(s). Wash out the housing(s) with warm
water and soap using a bottlebrush and then rinse thoroughly with clear water to flush away any soap
residue.
Note: Be sure all carbon pre- and post-filters are removed during the sanitizing procedure.
4. Insert the new cartridge(s) for the specific model.
Caution: Do not touch the filter(s) with your bare hands. Peel the wrapper and use as a sleeve to
prevent contamination. Wearing clean latex gloves can help prevent hand contact.
5. Pour 1 teaspoon (5 mL) of chlorine bleach directly down the center of the pre-filter cartridge so it will
collect in the small cuplike centering device in the bottom of the housing. Keep the housing upright
when attaching to the appliance to prevent spilling.
Note: For model H3000 and LC 30, flush the Carbon Pre-Filter to remove the carbon fines. This will
prevent fouling of the membrane. Pour 1 teaspoon (5 mL) of chlorine bleach into the top of the flushed
Carbon Pre-Filter cartridge.
6. Open the feed water valve and let the water run to the drain until there is a strong chlorine odor at the
end of the drain line. Shut off the feed water and let the RO sit for twenty minutes.
7. After twenty minutes, open the feed water valve and let the RO run for two to five hours.
8. Empty the tank and allow the appliance to refill. The water is now ready for use.
Sanitize the Storage Tank
The two options outlined below are the most convenient ways to sanitize the storage tank of your drinking water
appliance. Other methods may be used but require more complex procedures and apparatus typically used by
a professional Hague service technician.
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