GE Merlin User Manual

SYSTEM PERFORMANCE 13
Rev C
HOW TO DETERMINE RATE OF FLOW FROM THE MERLIN SYSTEM - NORTH AMERICAN
Example
Inlet Water TDS (measured) 300 ppm
Inlet Water Temperature 50°F
Inlet Pressure 60 psi
3/8-inch Tubing 15 ft long
Obstructions in Permeate Line One 90° elbow
Elevation Difference Between Merlin and Faucet 6 ft.
Post Filter? Yes
Faucet? Yes
Assigned Values
Pressure Drop per Obstruction 0.5 psi
Pressure Drop per Postfilter 3 psi
Pressure Drop in Elevation 0.43 psi per ft
(feet Faucet is above Merlin)
1. Determine the Inlet TDS = 300 ppm
2. Determine the Inlet Water Temperature = 50 °F
3. Determine the Net Driving Pressure of the Merlin system
Net Driving Pressure = Inlet Pressure - System Pressure Drop (Follow instructions below)
3A. Calculate the Flow Rate Adjustment Factor
This factor will be used with Table 1 to adjust the TDS of Inlet Water from 750 ppm to 300 ppm.
-
0.0002
(
300 ppm
)
+ 0.15 = 0.09 gpm
3B. Calculate the Tubing Pressure Drop
Inlet Pressure = 60 psi
Water Temp = 50°F
Use Table 1 to estimate flow rate, 750 ppm NaCl @ 50°F and 60 psi =
0.49 gpm
Adjust Table data for actual TDS using the Flow Rate Adjustment Factor 0.09 gpm
Tubing Flow Rate = 0.49 gpm
+ 0.09 gpm = 0.58 gpm @ 300 ppm NaCl
Use Figure 4 to determine the pressure drop for 1 ft. tubing = 0.138 psi
Tubing Pressure Drop for 15 ft = 15 x 0.138 psi = 2.07 psi
3C. Calculate the Obstruction Pressure Drop
1 obstruction (the elbow) X (0.5 psi) =
0.5 psi
3D. Calculate Elevation Pressure Drop
6 ft elevation X 0.43 psi/ft =
2.58 psi
3E. Calculate Postfilter Pressure Drop
1 postfilter X 3 psi =
3 psi
3F. Calculate Faucet Pressure Drop
60 psi - 2.07 psi - 0.5 psi - 2.58 psi - 3 psi = 51.85 psi
Use Table 1 to estimate flow rate, 750 ppm NaCl @ 50°F and 51.85 psi = 0.40 gpm
Adjust Table Data for actual TDS using the Flow Rate Adjustment Factor 0.09 gpm
0.36 gpm + 0.09 gpm = 0.45 gpm @ 300 ppm NaCl
e
8 and the Inlet Flow Rate o
f
0.49
gp
m to estimate the Faucet Pressure Dro
p
= 4.5 psi
3G. Calculate the System Pressure Drop
(System Pressure Drop = Tubing PD + Obstruction PD + Elevation PD + Postfilter PD + Faucet PD
2
.
0
7
p
si +
0
.5
p
si +
2
.5
8
p
si +
3
p
si + 4.5
p
si = 12.65 psi
3H. Determine the Net Driving Pressure Drop
(Net Driving Pressure = Merlin Inlet Pressure - System Pressure Drop)
60
p
si -
12
.
6
5
p
si = 47.35 psi
4. Determine the Merlin Flow Rate
Use Table 1 to estimate flow rate, 750 ppm NaCl @ 47.35psi and 50°F = 0.38gpm
Adjust Table Data for actual TDS using the Flow Rate Adjustment Factor 0.09 gpm
0.38 gpm + 0.09 gpm = 0.47 gpm
TOTAL MERLIN FLOW RATE = 0.47 gpm
g
gp p
pp ppp
pp
Actual results may vary. Membrane performance may vary ± 15%.

GE Merlin Specifications

General

Brand	GE
Model	Merlin
Category	Water Filtration Systems
Language	English