Viessmann B2TA, Installation And Service Instructions For Contractors

Page: 86 / 144

86
Fault code
displayed Const. Weather-
comp. System characteris-
tics Cause Measures
dF X Control mode without
room influence Lead break, room
temperature sen-
sor, heating circuit
3 (with mixer) Check room temperature
sensor for heating circuit
3 and remote control con-
figuration (see page 132)
E0 X Control mode External LON sub-
scriber fault Check connections and
LON subscribers
E1 X X Burner in a fault state Ionisation current
too high during cal-
ibration
Check gap between ioni-
sation electrode and burn-
er gauze assembly (see
page 37).
In open flue operation,
prevent high incidence of
dust in the combustion air.
Press reset button
R .
E3 X X Burner in a fault state Heat transfer too
low during calibra-
tion.
Temperature limiter
has shut down.
Ensure adequate heat
transfer.
Press reset button
R .
E4 X X Burner blocked 24 V power supply
fault Replace control unit.
E5 X X Burner blocked Flame amplifier
fault Replace control unit.
E6 X X Burner blocked System pressure
too low Top up with water.
E7 X X Burner in a fault state Ionisation current
too low during cali-
bration
Check ionisation elec-
trode:
■
Distance to burner
gauze assembly (see
page 37)
■
Electrode contamination
■
Connecting lead and
plug-in connections
Check flue system; reme-
dy flue gas recirculation if
required.
Press reset button
R .
E8 X X Burner in a fault state Ionisation current
lies outside the
permissible range
Check gas supply (gas
pressure and gas flow
switch), gas train and
connection pipe.
Check assignment of gas
type (see page 31).
Check ionisation elec-
trode:
■
Distance to burner
gauze assembly (see
page 37)
■
Electrode contamination
Press reset button R .
Troubleshooting
Fault codes
(cont.)
5773 216 GB
Diagnosis