20
e. Table 4.5 provides the flow rate and pressure drop
information that corresponds to various boiler
temperature rise values (
D
T). The pressure drop
shown is for the boiler only. If there is significant
system pressure drop in the piping, this should be
considered when specifying circulators.
f. Table 4.6 provides a list of recommended
circulators for boilers on a secondary loop of a
primary secondary system which uses water as a
heating medium.
g. Special consideration must be given if a glycol
based anti-freeze solution is used as a heating
medium. Propylene glycol has a higher viscosity
than water, therefore the system pressure drop will
be higher.
Table 4.6: Flow Rate & Pressure Drop for Various System Temperature Rise Values
D
T
(°F)
PFC-625
PFC-750
Flow Rate
Pressure Drop
Flow Rate
Pressure Drop
GPM
m³/hr
FT
mbar
GPM
m³/hr
FT
mbar
10
122.4
27.8
46.44
1388.23
147
33.39
49.7
1485.59
15
81.6
18.53
20.64
616.99
98
22.26
22.09
660.26
20
61.2
13.9
11.61
347.06
73.5
16.69
12.43
371.4
25
48.96
11.12
7.43
222.12
58.8
13.35
7.95
237.69
30
40.8
9.27
5.16
154.25
49
11.13
5.52
165.07
35
34.97
7.94
3.79
113.32
42
9.54
4.06
121.27
40
30.6
6.95
2.9
86.76
36.75
8.35
3.11
92.85
Table 4.7: Circulator Selection Chart (General Pump – Primary/Secondary Piping)
Circulator
Manufacturer
D
T
(°F)
PFC-625
PFC-750
Taco
20
VR15
VR15
Grundfos
UPS 50-60 F
UPS 50-8/4 F
Armstrong
E30.2
S55
Wilo
Stratos 2X3-35
Top S 2X35X3
Taco
25
VR15
VR15
Grundfos
UPS 43-100 F
UPS 50-60 F
Armstrong
E30.2
S55
Wilo
Top S 1.5X20X3
Stratos 2X3-35
Taco
30
VR3452
VR15
Grundfos
UPS 43-100 F
UPS 43-100 F
Armstrong
S55
S55
Wilo
—
—
Taco
35
VR3452
VR15
Grundfos
UPS 26-99
UPS 43-110 F
Armstrong
Compass 40-45
S55
Wilo
Star 17
Star 17
Taco
40
VR3452
VR3452
Grundfos
UPS 26-99
UPS 43-100 F
Armstrong
Compass R20-35
1B-0 & E16.2
Wilo
Star 17
Star 17
WATER PIPING & CONTROLS
The circulator sizing given is for primary/secondary
installations only. The system circulators must
be sized based on the flow and pressure drop
requirements of the system.
NOTICE