Green Heating Technology
12
possible loss) in an heating system already filled with an Anti freezing solution, the concentration
of the solution could have decreased and it could not guarantee the Anti freezing Protection.
• completely empty the hot and cold sanitary water system, including the sanitary circuit and the
DHW storage.
Remark:
the boiler is equipped with a system which protects the main components from the excep-
tional cases of mechanical lock, due to the inactivity in presence of water and scale. The anti-
locking function can’t work in Safety shut off mode, because of the lack of electrical supply.
Before re-igniting the boiler, have a technician check that the pump is not blocked due to inac-
tivity (for the technician: unscrew the plug in the centre of the cap to access the rotor shaft and
turn it with a screwdriver or other suitable tool).
Stand-by mode with anti-frost & anti-locking function
When the boiler is left in
OFF
mode during a period of inactivity, it will be protected against freezing by
several functions provided in the electronic controller, which heat the parts involved when the tempera-
ture falls below factory set values.
The anti-frost heating is accomplished by turning on the burner and pump.
In addition, when the boiler is in stand-by, it periodically activates the main internal components to
avoid rare cases of blockage due to inactivity in the presence of water and lime. This can also occur
when the boiler is locked (red lamp on) provided that the system pressure is correct.
In order for these systems to be active:
• the boiler must be receiving gas and electricity;
• boiler must be left on
OFF
mode (
shown on the display);
• system pressure must be correct (1÷1.5 bar in a cold state, minimum 0.5 bar)
In case of gas supply failure, or if the boiler locks for other reasons (the display shows
or
) the burner won’t turn on. Nevertheless, any time it is possible, the pump will work,
making the water circulate in the system and reducing in this way the possibility of freezing.
ATTENTION: the anti-frost protections cannot intervene in the absence of electricity. If you an-
ticipate this possibility, we recommend you add a good brand of anti-freeze to the heating sys-
tem, following the producer’s instructions.
We recommend to ask directly the installer/technician about the type of antifreeze product
put in the heating system during installation.
When the power comes back on, the boiler will check the temperature measured by the two
probes and, if it suspects freezing verified by a particular automatic control cycle, alarm 39 will
be triggered. For more details, see the relative description in the paragraph "Alarms - boiler
block" on page 32.
We recommend that you completely empty the hot and cold sanitary water system, including
the sanitary circuit and the DHW storage. The anti-frost function does not protect the sanitary
circuit outside the boiler.
