16
2.3.1 - VENTING OF THE C.H. SY-
STEM
An effective air vent shall be foreseen
in the highest point of the system. Inside
2.3.2 - BOILER AND HEATING
SYSTEM FILLING-UP &
DRAINING
For filling-up the system a filling tap has
to be foreseen on the system return pipe.
The filling-up can also be made through
the draining tap on the boiler return
manifold.
In both the cases, an approved hydraulic
disconnection system has to be fitted.
Before connecting the boiler, carefully
rinse out the whole system by running
water.
The boiler is equipped with its own drain-
ing tap (see fig. 2 for its position).
Never use such a tap to drain the sys-
tem, since the system dirt could gather
in the boiler and compromise its opera-
tion. The system itself shall be equipped
with its own draining tap, whose size de-
pends on the system capacity. The appli-
cation of a filter on the return pipe to the
boiler is advisable.
the boiler, there is an automatic air vent
on the flow manifold (see fig. 2). This air
vent is foreseen for the boiler, not for
the whole system.
Fig. 6.4
D.H.W. storage tank with loading pump installed on the secondary circuit, in parallel with the heating circuit.
Note: The Pr pump (heating pump) shall be off while the storage tank pump is running. In this case, the second digit of
parameter A shall be set to 2 (three-way valve).
For the connection of a boiler pump on the primary circuit or of a storage tank loading pump or a three-way valve, convenient
information can be found in the following table, which indicates the terminals supplied with 230 V in the different hypothesis.
The terminals 11 –13 will be supplied on tension 230 V in the case the pump after running is activated.
11 12 13
®
1
2
4
3
5
7
6
ST
O R
E
MO
DE
RE
SE
T
ST
EP
16
17
18
S
ee f
ig
.
16
Return
Flow
Filter
Boiler pump
See fig. 16
Mixing bottle
Heating Circuit
Heating
system pump
No return
valve
D.H.W. Circuit
Is there any heating demand?
YES/ NO
YES / NO
YES / NO
YES
NO
Is there any D.H.W. demand?
YES
NO
YES
NO
NO
D.H.W. priority system
configuration depending on 2
figure of “A Parameter”
(see paragraph 3.2.8.2)
nd
230 V - 50 Hz tension
is present at
terminals 16 - 18
parameter A = x 0
YES
NO
YES
YES
NO *
parameter A = x 1
YES
NO
NO
YES
NO *
parameter A = x 2
NO
YES
YES
YES
NO *
2
nd
figure
2
nd
figure
2
nd
figure
230 V - 50 Hz tension
is present at
terminals 11 - 13
