93
EN
4.6
Malfunction codes and possible solutions
LIST OF MALFUNCTION/FAULT ALARMS
Type No. Fault
Solution
AL
01 Smoke thermostat
- Contact the Technical
Assistance Centre
AL
02 Low water pressure in
system
- Restore pressure
- Check for any leaks in the
system
AL
04
Domestic hot water
sensor fault (return
sensor fault for T
models)
- Check connections
- Check the sensor is working
AL
05 Delivery sensor fault
- Check connections
- Check the sensor is working
AL
06 No flame detection
- Check the integrity of the
electrode and check that it is
not grounded
- Check gas availability and
pressure
- Check the integrity of the gas
valve and the card
AL
07 Sensor or safety
thermostat intervenes
- Check the sensor or
thermostat connections
- Deaerate the system
- Check the bleed valve
- Replace the sensor or the
thermostat
- Check that the pump impeller
is not blocked
AL
08 Fault in the flame
detection circuit
- Check the integrity of the
electrode and check that it is
not grounded
- Check the integrity of the gas
valve and the card
AL
09 No water circulating in
the system
- Check the rotation of the
pump rotor
- Check the electrical
connections
- Replace the pump
AL
10 Auxiliary sensor fault
- Check the hydraulic
configuration using "tS 0.2"
- Check the electrical
connection
AL
11 Gas valve modulator
disconnected
- Check the electrical
connection
AL
12
Domestic hot water
sensor fault in tank
mode
- Set the parameter tS 0.4
(Combustion configuration)
to 0
AL
13 Smoke probe
intervention
- Check the sensor is working
- Replace the smoke probe
AL
14 Smoke probe fault
- Replace the smoke probe
- Check the electrical
connection of the smoke
probe
- Contact the Technical
Assistance Centre
AL
15 Fan check cable
disconnected
- Check the connection cable
between the fan and the
board
AL
18 Condensate level fault
- Check for any clogging in
the pipe which takes the
condensate to the siphon
- Check that the siphon is not
clogged
AL
28
Maximum number of
consecutive resets
reached
- Wait 1 hour and try
unblocking the board again
- Contact the Technical
Assistance Centre
AL
30
Return sensor fault
(boiler sensor fault for
T models)
- Replace the return probe
- Check parameters
- Contact the Technical
Assistance Centre
AL
37 Fault due to low
network voltage
- Check the voltage
- Contact your network
provider
Type No. Fault
Solution
AL
40 Incorrect network
frequency detected
- Contact your network
provider
AL
41 Flame loss more than
6 consecutive times
- Check the ignition/detection
electrode
- Check the gas supply (open
valve)
- Check mains gas pressure
AL
42 Button fault
- Check that buttons are
working
AL
43 Open Therm
communication fault
- Check the OT electric
connection
AL
44 No flame valve opening
time sum anomaly
- Check for the presence of
water hammer on the hot
water system and, if present,
mount a water hammer
arrestor
- Check for any abnormal
requests on the room
thermostat
- Contact the Technical
Assistance Centre
AL
56
Lock for
∆T
delivery/
return over max limit
(open vent)
- Contact the Technical
Assistance Centre
AL
57
Lock for flow
temperature (FT)
check (open vent)
- Contact the Technical
Assistance Centre
AL
62 Self-calibrating
procedure is required
- Carry out the self-calibrating
procedure (see the specific
section)
AL
72 Incorrect positioning of
the delivery sensor
- Check delivery sensor
operation and position
AL
74 Second delivery sensor
fault
- Check second delivery sensor
operation and position
AL
77
EV2 SGV current max/
min absolute limits
error
- Check gas valve and board
AL
78 EV2 SGV current upper
limit error
- Check gas valve and board
AL
79 EV2 SGV current lower
limit error
- Check gas valve and board
AL
80
Fault on the valve
control logic line/valve
cable damaged
- Check gas valve and board
AL
81 Block due combustion
during start-up
- Check for blockage in
chimney
- Check air diaphragm (for BF
models)
- Check gas calibration
- Bleed the air from the gas
circuit
AL
82
Block due to numerous
combustion control
failures
- Check electrode
- Check outlets
- Check air diaphragm (for BF
models)
- Check gas calibration
AL
83 Irregular combustion
(temporary error)
- Check for blockage in
chimney
- Check air diaphragm (for BF
models)
- Check gas calibration
AL
84
Flow rate reduced
for (presumed) low
pressure on mains gas
- Check gas flow rate
AL
88 Internal error (board
component protection)
- Check the board is working
- Replace board
AL
89 Unstable combustion
feedback signal error
- Check electrode
- Check outlets
- Check air diaphragm (for BF
models)
- Check gas calibration