Temporary Switch-Off; Switching Off For Long Periods - Beretta CIAO AT Installer And User Manual

The level bar indicates whether the boiler is operating with a modulation range of 0 to 50%
= or 51% to 100% = .
The boiler continues to function until the temperatures set on the boiler are reached, or the
heat request terminates; it will then go back to standby.
In the event of shutdown due to a fault, the digital display will show the relevant error code
and, in the case of a non-volatile error, the fl ame lockout symbol
4.5 Warning lights and faults
The lockout condition stops the boiler from operating and is indicated on the display by a
fl ashing letter "A", followed by an error code and the appearance of the
In this condition, to restore normal operation the reset procedure must be carried out as
follows:
- press the RESET button
- wait for the ignition delay after the lockout:
t5, remaining time before restart more than 30 sec
or
t4, remaining time before restart less than 30 sec.
When the error is cleared, the relevant code disappears from the display and normal
operating mode is automatically restored. If the anomaly persists, you must contact the
Technical Assistance Service.
Table of anomalies needing RESET
Flame lockout alarm
Limit thermostat/Post-exchanger thermal fuse
Gas valve malfunction
Parasite fl ame/false fl ame
Air intake/fl ue gas exhaust obstructed
Loss of fl ame 3 times in the last 10 minutes
Poor combustion 3 times in the last 10 minutes
Gas valve fault/wiring fault
Fault A02
If, after RESET procedure, alarm A02 does not reset, it would be possible that the post-exchan-
ger thermal fuse, in series with the limit thermostat, has intervened. Ask for the intervention of
the Technical Assistance Center to resolve the fault.
The boiler could also detect the following "self-resetting" error situations which do not result
in a lockout condition. The boiler tries to reset automatically.
In this condition, the display shows the fl ashing letter "A", followed by an error code, but
there is no symbol.
When the error is cleared, the relevant code disappears from the display and normal
operating mode is automatically restored.
8
.
symbol.
RESET RESET
Self-resetting anomalies table
Low water pressure/condensate limit
CH NTC sensor
T Domestic hot water NTC sensor
Gas valve modulator
Insuffi cient water circulation
Poor combustion warning
Outdoor temperature sensor fault
Low supply voltage/abnormal mains frequency
Fan defective or not connected/fan wiring fault
CH NTC sensor over-temperature
Fault A04
- Low water pressure
together with the error code, the
to refi ll the system. Check the pressure value indicated by the water gauge: if it is less
than 0.5 bar press MODE to select the OFF mode and operate the fi lling tap (B) until the
pressure reaches a value between 1 and 1.5 bar.
When the automatic air vent cycle is fi nished or when it is interrupted by pushing RESET
button, press MODE to select the desired function.
If pressure drops are frequent, request the intervention of the Technical Assistance
Service.
After the system pressure (1 and 1.5 bar) compliance verifi ed, the continuous presence of A04
fault code can be due to the intervention of the condensate limit pressure switch (siphon or
condensate drain blocked). In this case, it is necessary to ask for the intervention of the
Technical Assistance to resolve the fault.
Fault A06
If alarm A06 persists in any operating mode, it means the DHW probe is faulty.
The boiler will carry on working normally, modulating to suit the fl ow sensor.
Burner OFF = Delivery temperature > DHW setpoint + 15 °C
Burner ON = Delivery temperature < DHW setpoint + 10 °C
To replace the DHW probe, contact the after sales service.
4.6

Temporary switch-off

In the event of temporary absences (weekends, short trips, etc.) press the MODE button,
the display will show OF.
A01
A02
A16
While the electrical supply and the fuel supply remain active, the boiler is protected by the
systems:
A11
- CH anti-freeze : this function is activated if the temperature measured by the outlet fl ow
A03
sensor drops below 5 °C. In this phase, the circulator is activated. If the boiler is not in
A12
lockout, the burner is also activated at minimum output until the delivery water tempera-
ture reaches 30°C.
A83
During the antifreeze cycle the display shows F08.
A82
- DHW anti-freeze: the function is activated if the temperature measured by the domestic
water sensor drops below 4° C. In this phase, the circulator is activated. If the boiler is
not in lockout, the burner is also activated at minimum output until the delivery water
temperature reaches 40°C.
During the antifreeze cycle the display shows F09.
4.7

Switching off for long periods

If the boiler is not going to be used for a long period, perform the following operations:
- press the MODE button and select OF
- set the system's main switch to "off"
- turn off the fuel and water taps of the heating and domestic hot water system.
symbol fl ashes on the display to indicate the need
B
MODE MODE
A04
A07
A06
A17
A18
A23
A48
A80
A34
A74