Fault code
Fault
Limit thermostat fault with
F50 - F53
parameter b06 = 1 or 4
Maximum number of con-
A64
secutive Resets excee-
ded
F62
Calibration required
Specific combustion con-
A88
trol errors or gas valve
Specific combustion con-
F65 ÷ F98
trol errors
Specific combustion con-
A65 ÷ A97
trol errors
Too many SW errors or
A98
error occurred during
board replacement
A99
Generic error
Specific flame combustion
F96
error
A44
Multiple requests error
Parasite flame signal after
A80
valve closing
284
EN
Possible cause
No/poor water circulation
in the system
Air in the system
Incorrect parameter
Maximum number of con-
secutive Resets exceeded
New card or boiler not yet
calibrated
Calibration activation with
burner lit.
Combustion problem,
faulty gas valve or PCB
Fume ducts obstructed.
Low gas pressure.
Condensate trap blocked.
Fumes recirculation or
combustion problem
Fume ducts obstructed.
Low gas pressure (A78 -
A84).
Condensate trap blocked.
Fumes recirculation or
combustion problem
Board replacement
Fume ducts obstructed.
Low gas pressure.
Condensate trap blocked.
Fumes recirculation or
combustion problem.
PCB hardware or software
error
Unstable flame or unstable
flame signal after ignition.
Repeated short-term
requests
Electrode problem.
Gas valve problem.
PCB problem.
cod. 3540000251 - Rev. 00 - 03/2024
ALHENA C
Cure
Check the circulating pump and hea-
ting system
Vent the system
Check the correct parameter setting
Disconnect the power supply to the
boiler for 60 seconds and then reins-
tate the boiler
Do complete manual calibration
Reset the fault and do complete
manual calibration.
If necessary, replace the gas valve or
PCB.
Check that the fume ducts and the
condensate trap are not blocked.
Check the correct gas supply pres-
sure.
Do a manual calibration to adjust the
CO
. If necessary, do a complete
2
manual calibration.
If the problem persists, replace the
PCB.
Check that the fume ducts and the
condensate trap are not blocked.
Check the correct gas supply pres-
sure.
Do a manual calibration to adjust the
CO
. If necessary, do a complete
2
manual calibration.
If the problem persists, replace the
PCB.
Reset the fault and proceed with
complete manual calibration.
Initially solve the problem, reset the
fault and check correct ignition.
Do a complete manual calibration
and, if necessary, replace the PCB.
Reset the fault and check for correct
ignition. Do a complete manual cali-
bration and, if necessary, replace the
PCB.
Check the gas supply, fume ducts
and condensate drain. Check the
correct position and state of the elec-
trode After about 3 minutes the error
is reset.
Check if there are pressure peaks in
the DHW circuit. If necessary, modify
parameter b11.
Check the correct position and condi-
tion of the electrode.
Check the PCB.
Check the gas valve and replace it if
necessary.