Figure 54
Estimated head loss of boiler loop piping and recommended circulators.
Figure 55
Estimated head loss of boiler loop piping and
recommended circulators.
8
7
6
5
4
3
2
1
0
0
2
4
6
8
10
12
14
16
155
70/110
70/110 Models
155 Model
Flow Through Heat Exchanger and Near-Boiler Piping (GPM)
Pressure Dr
op (ft.
w
.c.)
Part number 550-142-190/1218
49
Primary/Secondary System piping
(continued)
T (°F)
Flow
(GPM)
HEAD
(ft. w.c.)
Circulators
Taco
(Standard)
Taco
(3-speed)
Grundfos
Wilo
B&G
(Standard)
B&G
(3-speed)
Armstrong
Model 70 (70,000 Btu/hr)
20
6.5
3.6
007 *
007 (Lo)*
UPS 15-58
(Spd 1)
Star S 21 FX
(Spd 2)*
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 2)*
30
4.3
2.0
007 *
007 (Lo)*
UPS 15-58
(Spd 1)*
Star S 21 FX
(Spd 1)*
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 1)*
40
3.3
1.3
007 *
007 (Lo)*
UPS 15-58
(Spd 1)*
Star S 21 FX
(Spd 1)*
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 1)*
Model 110 (110,000 Btu/hr)
20
10.1
7.1
007
0015
(Med)
UPS 15-58
(Spd 3)*
Star S 21 FX
(Spd 3)*
NRF-22
NRF-25
(Spd 1)
Astro 230
(Spd 3)
30
6.7
3.8
007 *
007 (Lo)
UPS 15-58
(Spd 1)
Star S 21 FX
(Spd 2)*
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 2)*
40
5.1
2.5
007 *
007 (Lo)*
UPS 15-58
(Spd 1)*
Star S 21 FX
(Spd 1)
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 1)*
Model 155 (155,000 Btu/hr)
20
14.3
6.1
007
0015 (Hi)
UPS 15-42F
(Spd 3)
Star S 21 FX
(Spd 3)
NRF-22
NRF-25
(Spd 3)
Astro 250
(Spd 3)
30
9.5
2.7
007 *
007 (Med)
UPS 15-58
(Spd 2)*
Star S 21 FX
(Spd 2)
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 2)*
40
7.2
1.5
007 *
007 (Lo)*
UPS 15-58
(Spd 1)*
Star S 21 FX
(Spd 1)
NRF-22*
NRF-25
(Spd 1)*
Astro 230
(Spd 1)
* Due to the low pressure drop of the heat exchanger, these pumps should be throttled in order to achieve the listed fl ow rate.
System water piping methods
Near boiler piping
1. Connect boiler to system only as shown in
Figure 52, page 47 and Figure 53, page 48 . The
primary/secondary piping shown ensures the boiler
loop will have suffi cient fl ow.
2. Select a boiler loop temperature rise from
Figure 54 . The table indicates the fl ow and head loss
characteristics at that temperature rise and suggests
potential circulators. Circulators of other brands
not listed (Wilo, Armstrong, B&G)are acceptable
if they meet the fl ow and head requirements of
the design.
Verify that the boiler loop piping matches
closely with the listed criteria in the
NOTICE
below. If near boiler piping is
different, calculate head loss separately
using heat exchanger pressure drop
information from Figure 49, page 44 and
match to an appropriate pump.
The pressure drops shown are for
near boiler piping as illustrated in
Figure 52, page 47 and Figure 53, page 48
with 20 feet of straight piping.
®
S
ERIES
2
G
AS
-
FIRED
WATER
BOILER
—
Boiler Manual
