22
0
0,4
0,2
0,6
0,8
1
1,4
1,2
1,6
1,8
2
2,4
2,2
2,6
2,8
3
3,4
3,2
3,6
3,8
4
4,4
4,2
4,6
4,8
5
5,4
5,2
5,6
5,8
6
0
2000
4000
6000
8000
10000
12000
14000
16000
20000
22000
24000
28000
30000
32000
34000
36000
38000
40000
42000
44000
46000
48000
50000
52000
54000
18000
900
770
660
440
550
Portata (l/h)
Pe
rd
ite
d
ic
ar
ic
o
(m
/H
)
2
O
Instructions for the installer
3.11 DETERMINING THE PRIMARY
CIRCUIT PUMP OR BOILER PUMP
Immergas provides a series of primary rings complete with an accurately
sized pump, if alternative solutions are being used, the boiler pump
must have a head that is capable of ensuring the flow rates represented
in the "Water side head losses" graph.
The table below roughly indicates the flow rates of the pump based
on the Δt of the primary circuit if the installation is equipped with a
hydraulic separator.
The pumps must be determined by the installer or
designer based on the data for the boiler and system.
The resistance curve on the water side of the boiler is
represented in the table provided below.
The pump is not an integral part of the boiler.
It is advisable to choose a pump with a flow rate and
head of approximately 2/3 of its typical curve.
EXAMPLE:
For a ΔT 20K, of an ARES 900 Tec the maximum
required flow rate is 36,289 l/h.
From the head loss graph it is possible to deduce that
the pump must ensure a head of at least 1.8 m/H
2
O.
3.12 BALL VALVES
It is advisable to install cut-off ball valves on the flow and return pipes
of the system.
ATTENTION!
NEVER CUT OFF SAFETY DEVICES FROM THE
GENERATOR,
such as the safety valve and expansion
vessel.
In this way the boiler, during scheduled/unscheduled
maintenance, can be disconnected or emptied without
emptying the entire system.
Power in kW
440
550
660
770
900
Maximum flow rate in l/h (Δt = 15 K)
24326
30404
36487
42570
48647
Nominal requested flow rate in l/h (Δt = 20 K)
18243
22804
27365
31926
36487
Secondary circuit
NOTE: It is always advisable to set up a hydraulic compensator
between the boiler circuit and the system circuit. It becomes
ESSENTIAL if the system requires greater flow rates than the
maximum allowed by the boiler, i.e. ∆t below 15K.
Flow rate (l/h)
H
ead l
oss (m/H
2
O)
