lp-666 Rev. 003 Rel. 001 Date 2.25.20
18
Table 5 - Pressure Drop at Various Temperature Rises
In addition, the boiler heat exchanger has a minimum total water flow rate that must be taken into account when sizing the circulator.
Pressure drops are listed in the table below.
The boiler heat exchanger does have a pressure drop which must be considered in system design.
G. Circulator Sizing
Table 6 - Multiple Boiler Manifold Piping - NOTE: Table based on water velocity less than Five (5) feet per second.
The chart below represents the combined flow rates and pipe sizes when using multiple boilers to design the manifold system for the primary
circuit. To size, simply add up the number of boilers and the required flow rates for the system design temperature.
Example: (5) 1000 boilers with a design of 30
o
F temperature rise with each boiler having an individual flow rate of 64 GPM. To correctly size
the manifold feeding these boilers, you would need a pipe size of 6”.
Model
20
o
F
30
o
F
40
o
F
GPM
Ft / Hd
GPM
Ft / Hd
GPM
Ft / Hd
400
39
12.0
26
7.2
19
4.0
500
48
11.4
32
5.4
24
3.2
650
63
11.5
42
6.2
31
4.0
800
77
12
52
6
39
3
1000
96
14.0
64
7
48
4.7
1500
146
16
97
7.6
73
4.7
2000
194
21
129
11.5
97
6.7
Model
Number of Units and Recommended Common Header Pipe Sizes in Inches
2
3
4
5
6
7
8
400
3
3
4
4
5
5
5
500
3
4
4
5
5
5
6
650
4
4
5
5
6
6
6
800
4
5
5
6
6
8
8
1000
4
5
6
6
8
8
8
1500
5
6
8
8
8
10
10
2000
6
6
8
8
10
10
12
ELX-2000
ELX-1500
ELX-1000
ELX-800
ELX-650
ELX-500
ELX-400
0
5
10
15
20
25
30
0
10
20
30
40
50
60
70
80
90 100 110 120 130 140 150 160 170 180 190 200 210
Pr
essu
re Lo
ss
(Fe
et
of
H
ea
d)
+/
-10%
Flow Rate (GPM)
ELX-400
ELX-500
ELX-650
ELX-800
ELX-1000
ELX-1500
ELX-2000
Figure 10 - Pressure Drop through the Boiler