Viessmann Vitovalor PT2 E11T Installation And Service Instructions Manual page 106

Troubleshooting
Fault messages for gas condensing module
Fault number System characteristics
on the display
F.65 Burner in a fault state
F.66 Burner in a fault state
F.67 Burner in a fault state
F.68 Burner in a fault state
106
(cont.)
Cause
Flame signal is not
present or insufficient at
burner start.
No ignition spark
Ionisation current lies out-
side the permissible range
Flame signal is already
present at burner start.
Measures
Check gas supply (gas pressure
and gas flow switch).
Check gas train.
Check system for condensate
backup. Check condensate drain.
Note
Avoid water damage. Detach fan
unit before removing the burner.
Check ionisation electrode and
connecting cable.
Check ignition:
Connecting cables to ignition
■
module and ignition electrode
Ignition electrode gap and con-
■
tamination (see page 72).
Check ignition electrode for bro-
■
ken insulation.
Reset burner.
Check connection cables and
leads from ignition module and ig-
nition electrode.
Check for a voltage of 230 V~ at
plug 54 on the ignition module dur-
ing the ignition phase (see
page 196).
Check whether the ignition elec-
trode insulation is damaged.
Check gas supply (gas pressure
and gas flow switch), gas train and
connecting cable.
Check ionisation electrode for the
following:
Distance to burner gauze assem-
■
bly (see page 72)
Contamination on electrode
■
Reset burner.
Check ionisation electrode and
connecting cable.
Check system for condensate
backup. Check condensate drain.
Note
Avoid water damage. Detach fan
unit before removing the burner.
Reset burner.