Your PuROMax RO system contains filters and membranes which must be replaced periodically for proper operation.
(Please see page 1 for general change out recommendations.)
Note: Change-out procedures may be amended depending on source water conditions.
To change filters and membranes follow these procedures:
1. Only use PuROMax brand replacement filters and parts. Not doing so could void any warranty
2. Close feed water valve by turning it clockwise.
3. Open faucet to allow holding tank to drain.
4. Loosen and remove filter housings using wrench provided and discard cartridges and or membrane.
5. Wash the inside of the housings using mild detergent and soft cloth. Thoroughly rinse all soap before reassembly.
6. Replace filter cartridges and membrane before sanitizing system.
Note:
The system should be sanitized before installing the activated carbon post filter cartridge.
Sanitizing instructions
To sanitize system follow these procedures with the feed water valve closed:
1. Close feed water valve.
2. Open faucet to drain storage tank to sink.
3. Remove pre-filters & membrane from housings.
4. Use 5-1/4% unscented bleach, like Clorox.
5. Add one cap (2 tsp or 10 ml) of bleach to each pre-filter housing and the membrane housing.
6. Carefully reinstall housings without sediment, carbon pre-filter or membrane installed.
7. Slowly open feed water valve to allow water to mix with bleach and refill the housings and tank.
8. Open faucet to allow water to fill lines. Close faucet when water begins to drip from spout.
9. Let system stand for approximately 15 minutes.
10. After fifteen minutes do in the following order:
Close feed water valve.
Close holding tank valve while faucet is open to release pressure.
11. Carefully remove housings and empty them.
12. Remove protective wrap from pre-filters and membrane and install them in the appropriate filter housings. Hand
tighten and snug with wrench if necessary.
13. Replace post carbon in-line filter if necessary.
Note
: Be sure to check o-rings are in place when installing cartridges in filter housings. Damaged or incorrectly placed o-
rings will cause leaks.
14. Disconnect product water tubing from the holding tank and put 50 drops of bleach into the tubing. Reconnect tubing.
15. Slowly open feed water valve. When water begins to drip from faucet, close faucet and open holding tank valve.
16. Discard the first two tanks of water produced,
as they contain chlorine.
Do not use this water.
17. When faucet is first opened air and carbon powder may be noticed. This is normal. Allow filter to flush.
Water quality
Water quality from an RO system is normally determined with a TDS Meter, which measures
total dissolved solids
in
water, measuring conductivity. The results are normally measured in parts per million or milligrams per liter. Fewer
dissolved solids results in higher quality water. RO membranes are rated by the amount of dissolved solids they reject,
expressed as “rejection percentage”. For example if feed water contains 100 ppm of dissolved solids and the product
water after the membrane has 10 ppm of dissolved solids, the rejection rate is 90%.
The formula is as follows:
Percent rejection =
Feed water TDS
– Product water TDS X 100%
Feed water TDS
Water production
Product water rate
Usable water production from an RO system is designated
product water rate,
produced on a daily basis. The rate is
normally described in gallons per day (gpd) or milliliters per minute (ml/min.).
Reject water rate
The flow of water to drain is designated as
reject water rate,
as measured in gallons per day (gpd) or milliliters per minute
(ml/min.).
Using a graduated cylinder the formulas are:
Milliliters per minute X 0.38 = gallons per day
Ounces per minute X 11.2 = gallons per day
