39
Displayed
fault code
System characteris-
tics
Cause Measures
F4 Burner in a fault
state
No flame signal de-
tected
Check the ignition/ionisa-
tion electrodes and con-
necting leads, check the
gas pressure, check the
gas train, check the igni-
tion and ignition module.
Turn ON/OFF switch
8
off and on again (or reset,
see F2).
F6 Burner in a fault
state
Flue gas monitor
has responded
Check flue gas monitoring
sensor (see page 43).
Turn ON/OFF switch
8
off and on again (or reset,
see F2).
F30 Burner blocked Short circuit, boiler
water temperature
sensor
Check boiler water tem-
perature sensor (see
page 43).
F38 Burner blocked Lead break, boiler
water temperature
sensor
Check boiler water tem-
perature sensor (see
page 43).
F50 No DHW heating Short circuit, cylin-
der temperature
sensor (gas sys-
tem boiler)
Check sensor (see
page 43).
F51 No DHW heating Short circuit, outlet
temperature sen-
sor (gas combi
boiler)
Check sensor (see
page 43).
F58 No DHW heating Lead break, cylin-
der temperature
sensor (gas sys-
tem boiler)
Check sensor (see
page 43).
F59 No DHW heating Lead break, outlet
temperature sen-
sor (gas combi
boiler)
Check sensor (see
page 43).
Troubleshooting
Fault indicators on the display
(cont.)
5848 649 GB
Service