Hydronic piping – Lochinvar CREST 3.5 User Manual
Page 25
Installation & Operation Manual
5
Hydronic piping
(continued)
It is required that boiler piping systems
utilize Primary/Secondary or Full Flow
configurations as shown in FIG.’s 5-2
thru 5-5. The use of other boiler piping
configurations could result in improper
building and system flow rates leading to
inadvertent boiler high limit shutdowns and
poor system performance.
NOTICE
The pressure drop reflected in FIG. 5-1 is
for the boiler only. Additional allowances
must be made for piping, especially if
sizing pumps for Primary/Secondary
applications.
NOTICE
TEMPERATURE RISE APPLICATIONS
Model
BOILER
CONNECTION SIZE
20°F 40°F
60°F
GPM
FT/HD
GPM
FT/HD
GPM
FT/HD
FB 1500
4"
138
3.4
69
1.5
46
1.0
FB 2000
4"
184
4.1
92
1.6
61
1.0
FB 2500
4"
230
4.6
115
1.3
77
0.7
FB 3000
4"
277
5.6
138
1.2
92
0.7
FB 3500
4"
323
7.5
161
1.2
108
0.7
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
0
50
100
150
200
250
300
350
FBN1500
FBN2000
FBN2500
FBN3000
FBN3500
Flow Rate (GPM)
P
ressu
re
D
ro
p
(F
eet
o
f H
e
ad
)
CREST Pressure Drop Curve
Figure 5-1 Pressure Drop vs. Flow
Table 5A Sizing Information for Temperature Rise Applications_20°F, 40°F and 60°F
25
Circulator sizing
The Crest heat exchanger does have a pressure drop, which must be considered in your system design. Refer to the graph in
FIG. 5-1 for pressure drop through the Crest heat exchanger.
[Based on 92% AHRI Effi ciency]