System Water Piping Methods - Weil-McLain Series 2 Manual

® S
ERIES
Primary/Secondary System piping

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.
Figure 54 Estimated head loss of boiler loop piping and recommended circulators.
Flow HEAD
¨
T (°F)
(GPM) (ft. w.c.)
20 6.5 3.6
30 4.3 2.0
40 3.3 1.3
20 10.1 7.1
30 6.7 3.8
40 5.1 2.5
20 14.3 6.1
30 9.5 2.7
40 7.2 1.5
* Due to the low pressure drop of the heat exchanger, these pumps should be throttled in order to achieve the listed fl ow rate.
Part number 550-142-190/1218
2
-
G
AS FIRED WATER BOILER
Taco Taco
(Standard) (3-speed)
Model 70 (70,000 Btu/hr)
007 * 007 (Lo)*
007 * 007 (Lo)*
007 * 007 (Lo)*
Model 110 (110,000 Btu/hr)
0015
007
(Med)
007 * 007 (Lo)
007 * 007 (Lo)*
Model 155 (155,000 Btu/hr)
007 0015 (Hi)
007 * 007 (Med)
007 * 007 (Lo)*
— Boiler Manual
Figure 55 Estimated head loss of boiler loop piping and
recommended circulators.
8
7
6
5
70/110
4
3
2
1
0
0 2 4
Flow Through Heat Exchanger and Near-Boiler Piping (GPM)
Circulators
Grundfos Wilo
UPS 15-58 Star S 21 FX
(Spd 1) (Spd 2)*
UPS 15-58 Star S 21 FX
(Spd 1)* (Spd 1)*
UPS 15-58 Star S 21 FX
(Spd 1)* (Spd 1)*
UPS 15-58 Star S 21 FX
(Spd 3)* (Spd 3)*
UPS 15-58 Star S 21 FX
(Spd 1) (Spd 2)*
UPS 15-58 Star S 21 FX
(Spd 1)* (Spd 1)
UPS 15-42F Star S 21 FX
(Spd 3) (Spd 3)
UPS 15-58 Star S 21 FX
(Spd 2)* (Spd 2)
UPS 15-58 Star S 21 FX
(Spd 1)* (Spd 1)
(continued)
155
6 8 10 12
70/110 Models
155 Model
B&G B&G
(Standard) (3-speed)
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22
(Spd 1)
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22
(Spd 3)
NRF-25
NRF-22*
(Spd 1)*
NRF-25
NRF-22*
(Spd 1)*
14 16
Armstrong
Astro 230
(Spd 2)*
Astro 230
(Spd 1)*
Astro 230
(Spd 1)*
Astro 230
(Spd 3)
Astro 230
(Spd 2)*
Astro 230
(Spd 1)*
Astro 250
(Spd 3)
Astro 230
(Spd 2)*
Astro 230
(Spd 1)
49