19
1-28
B
A
C
D
INS
TALLER
US
ER
MAINTEN
AN
CE TECHNI
CI
AN
H
ea
d (kP
a)
A+B = Head available with by-pass closed
B = Head available with by-pass open
C+D = Power absorbed by the pump with by-pass open (dotted area)
D = Power absorbed by the pump with by-pass closed (dotted area)
Ci
rcu
la
to
r p
um
p a
bs
or
be
d p
ow
er (
W
)
Flow rate (l/h)
Total head available to the system.
Speed 9
Speed 9
Speed
5
1.26 CIRCULATION PUMP.
The boilers are supplied with a variable speed
circulator pump.
In the central heating mode, the following op-
erating modes are available and can be selected
from the “P.C.B. programming” menu.
NOTE.:
the ∆T can be controlled compatibly
with the characteristics of the central heating
system and of the boiler.
•
Proportional head (
∆
T = 0):
the circulator
speed varies according to the power emitted
by the burner, the greater the power the greater
the speed.
•
∆T Constant (∆T = 5 ÷ 25 K):
the pump speed
varies to maintain the ∆T constant between the
system flow and return according to set value
K (
∆T = 15 Default)
.
•
Fixed (5 ÷ 9):
by setting parameters “A3” and
“A4” at the same value, the pump operates at
constant speed.
N.B.:
for the boiler to work properly, it is not
allowed to drop below the minimum value
indicated above.
In domestic hot water mode, the circulator pump
always runs at full speed.
Pump release.
If, after a prolonged period of
inactivity, the circulation pump is blocked, turn
the motor shaft using a screwdriver. Take great
care during this operation to avoid damage to
the motor.
By-pass Regulation (part. 21 Fig. 1-29).
The
boiler leaves the factory with the by-pass open.
If necessary, the by-pass can be regulated to
system requirements from minimum (by-pass
closed) to maximum (by-pass open). Adjust
using a flat head screwdriver, turn clockwise
and open the by-pass, anticlockwise it is closed.
1.27 KITS AVAILABLE ON REQUEST.
• System shut-off valve kits with or without
inspection filter (on request). The boiler is
designed for installation of system interception
cocks to be placed on flow and return pipes
of the connection assembly. This kit is very
useful for maintenance because it allows to
empty just the boiler without having to empty
the entire system. Moreover, the version with
filter preserves the functioning characteristics
of the boiler thanks to its inspectionable filter.
• System zone control unit kit (on request). If
the heating system is to be divided into several
zones
(max. three),
in order to interlock them
with separate adjustments and to keep water
flow rate high for each zone, Immergas supplies
zone system kits by request.
• External storage tank unit coupling kit (on
request). If the production of DHW is required
as well as room central heating, on request Im-
mergas supplies a kit made up from an external
cylinder unit and everything necessary for
adaptation of the boiler
• Polyphosphate dispenser kit (on request). The
polyphosphate dispenser reduces the formation
of lime-scale and preserves the original heat
exchange and domestic hot water production
conditions. The boiler is prepared for applica-
tion of the polyphosphate dispenser kit.
• Relay board (on request). The boiler is prepared
for the installation of a relay card that allows
to increase the features of the appliance and
therefore functioning possibilities.
• Cover kit (on request). If installed outdoors in a
partially protected place with direct air intake,it
is compulsory to mount the appropriate top
protection cover for the correct functioning
of the boiler and to protect it from adverse
weather conditions.
• Cycloidal filter kit (on request). The magnetic
cycloidal filter is able to detect the ferrous resi-
dues present in the system's water. Thanks to
the two cocks in the kit, it facilitates mainte-
nance by cleaning the filter without having to
empty the circuit.
The above-mentioned kits are supplied complete
with instructions for assembly and use.
STD.002549/004
