Water Tec Int’l. Inc. Version 02A
6
PURIFIED WATER STORAGE AND DELIVERY SYSTEM
As previously discussed the R.O. product water is almost always delivered to an atmospheric storage tank.
Normally, such a storage tank is sized to provide sufficient water to cope with the number of hours of continuous use,
e.g., 8 hours, and 16 hours. In an exactly balanced system, the reverse osmosis unit would be running continuously.
However, in practice, demand fluctuates. A liquid level switch, which is provided with the R.O. unit, should be installed
at the full line of the tank. The liquid level switch turns off the R.O. when the tank is full. This way the unit only runs
when the tank is being emptied. Other types and styles of liquid level switches are available from your authorized
Water Tec distributor.
The purified water in the storage tank is distributed to the use points by means of a moderate pressure high
capacity centrifugal pump. This pump can be provided with a demand pressure switch, which turns on the pump
when it senses a drop in pressure (opening a faucet at the user point). Alternatively, it can be operated continuously,
with a pressure relief system to recirculate water back to the tank, when there is no demand. Such distribution
systems give very satisfactory service, because it avoids the detrimental repetitive on-off condition for the pump
motor. The pumps must never be allowed to run dry, since this will rapidly deteriorate the shaft seal and cause the
seal to leak. To prevent this the storage tank should be fitted with a low level switch, which shuts down the
distribution pump if the water level in the tank gets dangerously low.
