ALHENA C
Fault code
Fault
Exchanger protection
A09
intervention
Overtemperature protec-
F09
tion intervention
F10
Flow sensor fault
A11
Gas valve connection
F11
Return sensor fault
F12
DHW sensor fault
F13
Fume probe fault
Fume extraction duct
A14
safety device intervention
Supply voltage under
F34
180V
F35
Wrong supply frequency
System filling, with par.
A23
b07 = 2, over 5 minutes.
3 remote filling attempts
A24
in 24 hours
A26-F20 -F21
Water pressure switch
F40-F47-F51
fault
Incorrect system water
F37
pressure
F39
External probe fault
F19
Card parameter fault
Possible cause
No water circulation in the
system
Poor circulation and ano-
malous flow probe tempe-
rature increase
blocked exchanger
Flow sensor damaged
No water circulation in the
system
Air in the system
Sensor damaged
Wiring shorted
Wiring disconnected
Gas valve connector not
inserted.
Electrical connection bet-
ween control unit and gas
valve interrupted.
Gas valve damaged.
Sensor damaged
Wiring shorted
Wiring disconnected
Sensor damaged
Wiring shorted
Wiring disconnected
Probe damaged
Wiring shorted
Wiring disconnected
Fault A07 generated 3
times in the last 24 hours
Electric mains trouble
Electric mains trouble
Loss in system
Loss in system
Wrongly configured para-
meter
System pressure problems
(transducer)
b06 set to 3
Pressure too low
Water pressure switch
damaged or not connected
Probe damaged or wiring
shorted
Probe disconnected after
activating the sliding tem-
perature
Wrong card parameter set-
ting
cod. 3540000251 - Rev. 00 - 03/2024
Cure
Check the circulating pump and hea-
ting system
Vent the system
check the exchanger and system
Check correct positioning and opera-
tion of the flow sensor and replace it if
necessary
Check the circulating pump and hea-
ting system
Vent the system
Check the wiring or replace the sen-
sor
Insert the connector
Check the wiring
Replace the gas valve
Check the wiring or replace the sen-
sor
Check the wiring or replace the sen-
sor
Check the wiring or replace the fume
probe
See fault A07
Check the electrical system
Check the electrical system
Check the system or the filling valve
Check the system
Check if parameter b04 is configured
correctly (default 0=pressure switch)
System pressure value outside set
limits (transducer)
Fill the system
Check the water pressure switch
Check the wiring or replace the sen-
sor
Reconnect the external probe or disa-
ble the sliding temperature
Check and if necessary modify para-
meter b15 to 3
EN
283