Fault messages in the display
Faults are indicated by a flashing fault
code with fault symbol "
U
" and the
reset key is illuminated.
For fault code explanations see the
following table.
Display fault
code
System char-
acteristics
Cause
Remedy
30
Burner
blocked
Boiler temperature
sensor shorted out
Check the boiler tem-
perature sensor (see
page 76).
38
Burner
blocked
Boiler temperature
sensor lead break
Check the boiler tem-
perature sensor (see
page 76).
51
No DHW heat-
ing
Draw off tempera-
ture sensor short
circuit
Check sensors (see
page 78).
59
No DHW heat-
ing
Draw off tempera-
ture sensor short
circuit
Check sensors (see
page 78).
b1
Control mode
Communication
fault
–
program-
ming unit (internal)
Check connections and
replace the programming
unit, if necessary.
b5
Control mode
Internal fault
Replace control unit.
E4
Burner
blocked
Fault
–
supply vol-
tage
Replace control unit.
E5
Burner
blocked
Internal fault
Check the ionisation
electrode and leads.
Press"Reset".
E6
Burner
blocked
Water pressure
too low
Top up water (see
page 66).
F0
Burner
blocked
Internal fault
Replace control unit.
Fault finding
(cont.)
71
Troubleshooting
58
62
670
GB
Service
