Millenium MRO-35, Operation Manual

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SECTION I.   INTRODUCTION 

  Your new Reverse Osmosis (R.O.) Drinking Water 

System uses a combination of filtration technologies 

to reduce unwanted contaminants in a water supply. 

The following steps combine to give you the best in 

clear sparkling drinking water: 

MECHANICAL FILTRATION/ACTIVATED 

CARBON

–The Sediment/Carbon Prefilter has 

been designed to reduce the larger particles 

such as silt, rust and scale. Its 5 micron 

(equal to 0.0002 inch) nominal rating helps 

to give maximum life to the R.O. Membrane.

The activated carbon in the Prefilter has been 

designed to reduce any chlorine that may be 

present in the feed water. This pretreatment is 

also necessary for membrane protection.

REVERSE OSMOSIS MEMBRANE

–The R.O. 

Membrane is the heart of the filtration system. 

It is designed to reduce the dissolved mineral 

content of the water. Minerals picked up in the 

environment by the water are measured as Total 

Dissolved Solids (TDS). In the Reverse Osmosis 

process, dissolved minerals are separated from 

the incoming water (Feed Water) to produce 

the product water (the Permeate). The excess 

minerals are rinsed to drain (the Reject Water). 

  The membrane is a specially constructed, fully 

aromatic polyamide film, and is classified as a 

Thin Film Composite (T.F.C.).

  The spiral wound construction of the R.O. 

Membrane provides maximum surface area 

for water production and is less susceptible 

to fouling by particulate matter, turbidity and 

colloidal materials. 

ACTIVATED CARBON

–The Activated Carbon 

Post Filter contains carbon particles with a vast 

network of pores. The tremendous surface 

area of these pores (typically 800–1200 square 

meters per gram of carbon) gives the carbon 

very good adsorptive sites for substances that 

contribute to tastes and odors. 

IN–LINE ACTIVATED CARBON POST FILTER

–

The In–Line Activated Carbon Post Filter is 

located after the Holding Tank and has been 

designed to reduce the tastes and odors that 

may pass through the system. It adds a final 

polish to the water. 

AUTOMATIC SHUTOFF VALVE

–The 

ASO Valve senses when the product water 

tank is full and closes the feed water supply to 

prevent excess reject water from going to drain 

when the unit is not producing water.

WATER QUALITY MONITOR

–The optional 

Water Quality Monitor has been integrated 

into the faucet base for instant monitoring at 

the touch of a button. The monitor compares 

the level of the Total Dissolved Solids in the 

incoming (feed) water versus the product water 

and calculates the percent rejection. The monitor 

is preset to indicate a level of 75% rejection. 

  A green light indicates that the percent rejection 

is at or above the set (desired) value and that 

the system is producing quality water. 

  An amber light indicates that the product water 

quality is less than acceptable. Because the 

Water Quality Monitor was designed to operate 

best while the system is making water, a false 

reading may occur if tested when your R.O. 

drinking water system is not making water. 

Please empty the storage tank, wait 15 minutes 

for the system to begin making water, and test 

your water quality again. If the Water Quality 

Monitor light is still amber, please contact a 

water treatment professional for service. The 

Water Quality Monitor requires a 9 volt battery, 

which is included. Systems not equipped with a 

Water Quality Monitor contain a Water Quality 

Test Kit.

IMPORTANT NOTICES:

This reverse osmosis system contains replaceable treatment components critical for effective performance. It is the 

user's responsibility to, and the manufacturer strongly recommends that the user, periodically test the product water 

to verify the system is performing satisfactorily. See the test kit(s) for sampling instructions.
This system is acceptable for treatment of influent concentrations of no more than 27 mg/L nitrate and 3 mg/L nitrite 

in combination measured as N and is certified for nitrate/nitrite reduction only for water supplies with a pressure of 

280 kPa (40 psig) or greater.
This system conforms to NSF/ANSI Standard 58 for pentavalent arsenic reduction. See the Performance Data 

Sheet and Arsenic Facts section for an explanation of reduction performance.

DO NOT USE WITH WATER THAT IS MICROBIOLOGICALLY UNSAFE OR OF UNkNOWN QUALITY, WITHOUT 

ADEQUATE DISINFECTION BEFORE OR AFTER THE SYSTEM.

Systems certified for cyst reduction may be used on disinfected water that may contain filterable cysts.