Culligan Aqua-Cleer Series Installation, Operation & Service Instructions With Part List page 26

Checking Quantity Produced
Measure and record both the flow rate and temperature of the product water. Record the temperature correction factor from
table 3, page 26, which corresponds to the measured flow rate to the 77°F (25°C) standard as follows:
Adjusted Flow Rate = Measured Flow Rate ÷ Temperature Correction Factor
As an example, if the above system is producing 24.15 gpd at 60°F, the Temperature Correction Factor from Table 3 is 0.69.
24.15 gpd ÷ 0.69 = 35 gpd @ 77°F
The TDS levels of the product and feed water were measured in the previous section. To accurately predict the performance of
the RO module, the feed water pressure must be adjusted to account for osmotic pressure. Calculate osmotic pressure
as follows:
Osmotic Pressure = 1 psi for every 100 mg/L TDS
From the previous example system: 1000 ÷ 100 = 10 psi Osmotic Pressure
Since osmotic pressure acts as back pressure against the RO process, it is subtracted from the measured feed water pressure
to determine the effective module pressure. Measure the feed water pressure and calculate the effective module pressure
as follows:
Effective Module Pressure = Measured Pressure - Osmotic Pressure
If the pressure measured from our example system is 60 psi: 60 - 10 = 50 psi Effective Module Pressure
Using the effective module pressure, read the standard product flow rate from flow graphs 2, 3 and 4. For our example system,
we find the standard product flow is 35 gpd at 50 psi. Comparing this to the adjusted flow rate, we find the example system
operating within the limits of the published standard.
Checking Quantity Stored
Following the guidelines below will allow you to predict the volume of water which will be stored by the tank as well as reduce
the risk of damage to the storage tank.
The storage tank uses a rubber bladder attached to the tank wall with air pressure on one side to push product water out of
the tank. This bladder is stretched when the tank is filled with water. Too much stretching can damage the bladder or pull it
away from the tank's wall causing failure. We've prepared a easy method to determine the proper air pressure based on the
application's requirements.
The 70% rule
We recommend that the tank never hold more than 70% of its internal volume as water. Table 2, page 25, lists the water
volumes versus tank size based on air pressure and product pressure. Values are listed for 5, 10 & 15 psi air pressure
settings. Note: Before using the table adjust the influent water pressure to product pressure.
Influent Water Pressure x 0.67 = Product Pressure
24 Culligan Aqua-Cleer Drinking Water Systems
® ®