Installation Guide

Part number 550-100-066/0608
23
g a s -f i r e d w at e r b o i l e r — Boiler Manual
Install water piping (continued)
Pump curves for typical circulators suggested for DHW 
loop
 Pipe sizing and head losses for DHW
applications
(H1=Ultra boiler head loss;
H2=piping head loss)
Flow
rate
Temp
rise
Pipe
size
H1 H2
GPM °F Inches
Boiler head
loss
Feet w.c.
Piping head
loss
Feet w.c.

3.5
(min) 41 1 1.4 0.8
7 20 1 6.6 2.7
9 16 1 11.6 4.2
10 14 1¼ 14.6 2.5

4.5
(min) 42 1 3.1 1.2
7 27 1 7.0 2.7
9 21 1 11.2 4.2
10 19 1¼ 13.6 2.5
13 14 1¼ 22.2 3.9

7.0
(min) 40 1¼ 3.6 1.3
9 31 1¼ 6.2 2.1
10.0 28 1¼ 7.7 2.5
13 21 1¼ 13.3 3.9
16 17 1¼ 20.5 5.7

10
(min) 41 1¼ 5.9 2.5
13 32 1¼ 9.4 3.9
16 26 1¼ 13.7 5.7
21 20 1½ 22.0 4.2
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14.5
(min) 40 1½ 4.6 2.1
18 32 1½ 6.5 2.9
21.5 27 1½ 9.2 4.4
29 20 1½ 15.5 7.4