23
INS
T
ALLER
US
ER
MAINTEN
AN
CE TECHNI
CI
AN
Error
Code
Anomaly signalled
Cause
Boiler status / Solution
24
Push button control
panel anomaly
The board detects an anomaly on the pushbutton panel
If normal conditions are restored the boiler
restarts without having to be reset (1).
25
Block due to
fl
ue
gas temperature
gradient
intervention
If the board detects a rapid increase in flue gas temperature probably due
to a blocked circulating pump or lack of water in the heat exchanger, the
boiler shuts down due to the flue gas temperature gradient trip.
Press the Reset button (1).
27
Insu
ffi
cient
circulation
This occurs if there is overheating in the boiler due to insufficient water
circulating in the primary circuit; the causes can be:
- low system circulation; check that no shut-off devices are closed on the
heating circuit and that the system is free of air (deaerated);
- pump blocked; free the pump.
Press the Reset button (1).
29
Flue probe anomaly
The board detects an anomaly on the flue gas probe.
The boiler does not start (1).
31
Loss of remote
control
communication
This occurs 1 minute after communication loss between the boiler and
the remote control.
Power cycle the boiler. If the Remote
Control is still not detected on re-starting,
the boiler will switch to local operating
mode, i.e. using the controls on the control
panel (1).
36
IMG Bus
communication
loss
Communication between the various components is interrupted due to
an anomaly on the boiler control unit, on the zone control unit or on
the IMG Bus.
The boiler does not satisfy the room heating
requests (1).
37
Low power supply
voltage
This occurs when the power supply voltage is lower than the allowed limits
for the correct boiler operation.
If normal conditions are restored the boiler
restarts without having to be reset (1).
38
Loss of
fl
ame signal
This occurs when the boiler is ignited correctly and the burner flame goes
out unexpectedly; a new ignition attempt is performed and if normal con-
ditions are restored, the boiler does not have to be reset (this anomaly can
only be checked in the list of errors present in the “Information” menu).
If normal conditions are restored the boiler
restarts without having to be reset (1).
43
Block due to loss of
continuous
fl
ame
signal
This occurs if the ''Flame signal loss'' error occurs many times in a row
within a preset period (38).
Press the Reset button, before restarting, the
boiler will run a post-ventilation cycle. (1).
44
Block for exceeding
the maximum accu-
mulated time, close
gas valve opening
This occurs if the gas valve remains open for longer than required for
normal operation, without the boiler switching on.
Press the Reset button (1).
45
ΔT high
If the board detects a sudden and unexpected rise in ΔT between the
system flow probe and return probe, the boiler limits the burner output
to prevent damaging the condensing module; when the correct ΔT has
been restored, the boiler returns to normal operation.
Make sure there is water circulating in the
boiler, that the pump is configured accord-
ing to system requirements and that the
return probe works properly (1).
46
Low temperature
safety thermostat
(optional)
During normal operation, if an anomaly causes excessive overheating of
the flow temperature in low temperature conditions, the boiler blocks.
In this case, after suitable cooling, it is pos-
sible to reset the thermostat (see relative
instructions sheet) (1).
47
Burner power
limitation
Should flue high temperature be detected, the boiler reduces power sup-
plied so as not to damage it.
(1).
49
High temperature
block on return
probe
This occurs when the heat exchanger return circuit reaches a temperature
that is too high.
Make sure that water circulates properly
in the boiler and that the three-way valve
works properly. Press the Reset button (C)
to eliminate it (1).
(1) If the shutdown or fault persists, contact an authorised company (e.g. Authorised Technical After-Sales Service).
