Reverse Osmosis

Our Reverse Osmosis (R/O) Systems are the most cost effective and reliable water treatment systems for municipalities and industrial facilities. We provide complete water purification solutions that insure quality and responsiveness to your water concerns.
Principles of Reverse Osmosis
R/O systems purify water by forcing pressurized water through reverse osmosis membranes. The small pores of these membranes allow only high quality water to permeate, while rejecting metals, slats, ionic and organic impurities. Suspended solids are removed by pre-filters, which are standard components on R/O systems.

Water temperature
Product water quality and production of any RO system is dependent on pressure and temperatures. Watts RO systems are rated at standard conditions of 77°F (25°C), 60 psi (4.2 bar) inlet pressure and 1,000 TDS feed water quality. Higher temperatures will result in more water passing through the membranes and increased water production. As a rule, at given pressures and TDS levels, for each one-degree change in water temperature the change in water production in approximately 2%.

Water temperatureProduction Factor*
(using thin film membranes)

*Percent of rated production

Water pressure
Watts commercial RO systems require a minimum of 10 psi feed pressure to function properly. The maximum pressure is 90 psi, and a pressure regulator must be utilized over 90 psi to reduce feed water pressure.

Feed/source water inlet requirements
The source water requirements shown below are essential for proper operation:

Inlet feed water requirements
Hardness<1 grain per gallon
Free chlorine0 ppm
T.D.S<1,000 ppm
pH3 – 11
Iron<0.01 ppm
Silica<25 ppm
Manganese<0.05 ppm
Turbidity<1 NTU
Temperature40°F – 95°F (4°C – 32°C)
Pressure10 – 90 psi (2.8 – 5.6 bar)

Operation instructions

  1. System location
    The RO system should be positioned on an elevated surface in an area sheltered from sun, wind and rain. The temperature in this area should be maintained, and should not fall below 35° F, nor greater than 95° F. If these limits are exceeded, damage to components may result and the warranty may be considered invalid. Sufficient space around the unit is important for easy maintenance.
  2. Plumbing
    The high-pressure pumps used require a continuous flow of water to the system. Minimum feed pressure is 10 psi.
  3. Feed water
    The RO systems use either copper or plastic piping for feed water. Iron and carbon steel pipes will increase the iron content of the raw feed water and negatively affect the RO system’s performance. Temperature of the feed must not exceed 95° F.
  4. Product water (permeate) line connection
    Connect the product water(permeate) line to the manifold on the back side of the system. This line should not have valves and should run as directly as possible to the storage tank.
  5. Concentrate (waste) line connection
    Connect the waste line (concentrate) to the manifold on the back side of the system. The waste from the system should not have valves and should not have an air break between it and the building drain system. The tubing or piping used for discharge of the concentrate should be run to an open drain in a free and unrestricted manner.
  6. Electrical 
    A properly sized electrical service is required.

Level controls
In most installation it is necessary to use the level switch connector wire to install a level control or an electrical switch to turn RO systems on and off based on the water level in the storage tank.

Never let pumps run dry. Operating pumps without sufficient feed water will cause damage. Feed pumps with filtered water only.

RO systems are equipped with particulate pre-filters for the removal of suspended particles down to five micron size. Change pre-filter cartridges at least every month or when there pressure differential of 10% or more that start-up pressure differential with clean cartridges.