111
Displayed
fault code
System characteris-
tics
Cause
Measures
EC
Burner in a fault
state
Parameter fault
during calibration
Press reset button
R
or
Replace boiler coding
card and press reset but-
ton
R
.
Ed
Burner in a fault
state
Internal fault
Replace the control unit.
EE
Burner in a fault
state
Flame signal is not
present or too
weak at burner
start
Check gas supply (gas
pressure and gas flow lim-
iter);
check gas train.
Check the ionisation elec-
trode and connecting
cable.
Checking ignition:
■ Connecting leads to
ignition module and
ignition electrode
■ Distance to ignition
electrode and contami-
nation (see page 40).
Check condensate drain.
Press reset button
R
.
EF
Burner in a fault
state
The flame is lost
immediately after it
has built (during
the safety time).
Check gas supply (gas
pressure and gas flow lim-
iter).
Check flue gas/ventilation
air system for flue gas
recirculation.
Check ionisation elec-
trode (replace if required):
■ Distance to burner
gauze assembly (see
page 40)
■ Contamination of elec-
trode
Press reset button
R
.
Troubleshooting
Fault codes
(cont.)
5412 755 GB
Service