132
Dis-
played
fault
code
Const.
Weath.-
comp.
System char-
acteristics
Cause
Measures
EF
X
X
Burner in a fault
state
Flame is lost
immediately
after it has
built (during
the safety
time)
Check gas supply
(gas pressure and
gas flow limiter).
Check flue gas/
ventilation air sys-
tem for flue gas re-
circulation.
Check ionisation
electrode (replace
if required):
■ Distance to burn-
er gauze assem-
bly (see page 46)
■ Contamination of
electrode
Press reset button
R
.
F0
X
X
Burner blocked Internal fault
Replace control
unit.
F1
X
X
Burner in a fault
state
Flue gas tem-
perature has
exceeded
limit
Check heating sys-
tem fill level. Vent
the system.
Press reset button
R
after flue system
has cooled down.
F2
X
X
Burner in a fault
state
Boiler water
temperature
sensor has
responded
Check heating sys-
tem fill level. Check
circulation pump.
Vent the system.
Check boiler water
temperature sen-
sor and connecting
cables.
Press reset button
R
.
Troubleshooting
Fault codes
(cont.)
5623 520 GB