The flow control features a concentrate flow control valve, a recycle flow control valve, and a
pressure gauge.
The proper adjustment of these valves is critical to the operation of the RO machine. The
concentrate valve determines the amount of rejected water leaving the machine, and
creates the operating pressure shown on the pressure gauge. The recycle valve returns
unused reject flow back into the inlet stream to the RO pump. It is important to balance the
operating pressure and the respective flows of these valves to ensure that your machine is
operating correctly. The pump has a fixed amount of flow produced, and the valves are the
control devices to distribute this fixed amount of flow produced. The pressure gauge is an
indicator of applied membrane pressure at the flows set by the valves.
4.8
Turn on the machine; allow the machine to operate for one minute to purge the air from the
machine. As you are operating, be sure to watch the pressure gauge on the flow control
center. The machine is designed to operate at maximum 225 psi.
NOTE : Do not allow the pressure to exceed 200 psi. If the pressure exceeds 200 psi, open
the concentrate flow valve until the pressure gauge shows 200 psi or less.
As the machine purges the air and fills with water, the pressure will gradually increase. You
should see water flowing from the permeate and concentrate outlets. If you do not see flow
from these points, turn the machine off and return to Section 4.1
CAUTION :
NEVER ALLOW THE MACHINE TO OPERATE WITHOUT
ADEQUATE FEEDWATER PRESSURE, AS THIS MAY CAUSE
SERIOUS MACHINE DAMAGE.
The concentrate flow control valve has a drilled orifice to ensure a predetermined amount of
flow and pressure in the closed position. This orifice is sized to operate the machine at 50%
recovery.
5.0
FLUSHING AND CLEANING
5.1
Flushing
The machine should be flushed weekly to remove sediment from the surface of the
membrane . To flush the unit:
5.1.1
Open the concentrate valve until the pressure gauge reads the pressure designated
on the nameplate. Normally this will be 50 psig (3.5 bar).
NOTE :
If pressure will not drop to specified pressure during flushing, the valve
must be cleaned.
5.1.2
Allow the machine to run at its designated pressure for 10 to 20 minutes.
5.1.3
Close the concentrate valve to its previous position and check to be sure a proper
concentrate flow rate is going to the drain.
5.1.4
The machine is ready to operate.