FAFCO Sunsaver - Example Pump Sizing Calculation

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27
Example Pump Sizing Calculation
APPENDIX B — Pump Sizing
Example Table 1: Head Loss Calculation Table for 2" PVC Fittings
Fitting Used
Equivalent Pipe Length
Head Loss of Fitting (ft) Quantity Used Totals
45° Elbow
2.7
8
= 22
90° Elbow
8.5
18
= 153
Sweep
3.6
0
= 0
Tee's
12
3
= 36
Total Fitting Equivalent Length (ft)
211
Feet of Straight Piping Used (ft)
80
Equivalent Sys Straight Pipe Length (ft)
291
SunSaver Eq Head
Loss (ft)
# Collectors on Roof/# Rows Average Bank Size Pressure Drop (ft)
8 / 2
4
20.4
System Dynamic
Head Loss
Calculation
System Flow Rate (GPM)
(#Collectors*0.1GPM/ft
2
ea.)
Head Loss/ft Piping (ft)
(from System Flow Rate)
Total Dynamic Head Loss (ft)
38.4 (round to 40)
0.028
8.1
Vertical Head Loss (ft)
24
Head Loss in other Pool Equipment (ft) 32 (~14 psi)
Total Head Loss (ft) 85 FT
Total Head Loss (psi) 36 PSI
Box A
Box B
Box C
Box D
Box E
Box F
Box G
Box H
Box I
Box J
Box K
Box L
Box M
Box N
Box O
Box P Box Q
Box R
Box U
Box S
Box T
Box V
Box W
Box X
(A*E)
(B*F)
(C*G)
(D*H)
(I+J+K+L)
(Box P result)
(M+N)
(Box Q*5.1  ea. panel)
(Table A2 from box S)
(T*O)
(Pump to top header height)
(R+U+V+W)
(X*0.43)
(total pipe length used)
Box Y
(Losses for lter, heater, etc.)
Example Table 2: Head Loss at Flow Rates in 2" PVC
Flow Rate (GPM) Head Loss/ft Piping (ft) Flow Rate (GPM) Head Loss/ft Piping (ft)
0 0.000 45 0.036
4.5 0.0005 50 0.043
8 0.001 55 0.053
10 0.002 60 0.060
15 0.004 65 0.070
20 0.008 70 0.079
25 0.010 75 0.091
30 0.017 80 0.102
35 0.018 85 0.114
40 0.028 90 0.126
2” PVC Acceptable for Flow Rate 2” PVC Not Recommended for Flow Rate