12
SYSTEM PERFORMANCE
Rev C
Use the flow rate worksheet located at the end of this document to
estimate flow from the Merlin.
In The Followiing Example:
A Merlin will be installed under the following conditions:
Table 1 - Merlin System Flow Rates (gpm), Based on 750 ppm NaCl Inlet Water
a
Net Driving Pressure
b
, psi [bar]
Temperature
°
F [
°
C]
75
[5.2]
70
[4.8]
65
[4.5]
60
[4.1]
55
[3.8]
50
[3.4]
45
[3.1]
40
[2.8]
35
[2.4]
80 [27]
1.03
0.95
0.88
0.81
0.74
0.67
0.60
0.53
0.46
70 [21]
0.89
0.83
0.77
0.71
0.65
0.58
0.52
0.46
0.40
60 [16]
0.77
0.72
0.66
0.61
0.55
0.50
0.44
0.39
0.33
50 [10]
0.63
0.59
0.54
0.49
0.45
0.40
0.36
0.31
0.26
a. To adjust data to actual conditions, multiply measured TDS by -0.0002 and add 0.15. Add answer to
Table data to achieve actual flow rate. Estimated flow change from 750 ppm NaCl =
-.0002 X measured TDS + 0.15
b. Net Driving Pressure = Flowing Inlet Pressure – System Pressure Drop
NOTE:
Pressure drop throughout the system is caused by such things
as frictional tubing losses, vertical tubing runs, post filter, faucet, and
obstructions. See section on system pressure drop for more detailed
information.
NOTE:
Actual system performance may vary due to manufacturing
tolerances and installation factors.
Inlet Water TDS
300 ppm
Inlet Water Temperature
50
°
F (10
°
C)
Flowing Inlet Pressure
60 psi (4.1bar)
3/8-inch Tubing Length
15 ft (4.6 m)
Obstruction(s) In Permeate Line
One 90
°
elbow
Elevation Difference Between Merlin And
Dispensing Location
6 ft (1.8 m)
Post Filter Used?
Yes
Faucet Used?
Yes
