Viessmann Vitovalor PT2 E11T Installation And Service Instructions Manual page 122

Troubleshooting
Fault messages for gas condensing module
Fault number System characteristics
on the display
F.452 Burner in a fault state
F.453 Burner in a fault state
F.454 Burner in a fault state
F.455 Burner in a fault state
F.456 Burner in a fault state
F.457 Burner in a fault state
F.458 Burner locked out
F.461 Burner locked out
F.462 Burner in a fault state
122
(cont.)
Cause
Error in scheduled pro-
gram run monitoring
Synchronisation error, se-
quence
Incorrect software version
Error in logical program
run monitoring
System status at system
start
Fan blocked
Internal error
Feedback signal of flue
gas damper at EM-EA1
(DIO) extension input pre-
venting burner start.
LPG safety valve (sole-
noid valve) at EM-EA1
(DIO) extension does not
open.
Measures
Check ignition electrodes and con-
necting cables.
Check ionisation electrode and
connecting cable.
Reset burner.
Check ignition electrodes and con-
necting cables.
Check ionisation electrode and
connecting cable.
Reset burner.
Load the correct software version
for the burner control unit (BCU).
Check ignition electrodes and con-
necting cables.
Check ionisation electrode and
connecting cable.
Reset burner.
Check ignition electrodes and con-
necting cables.
Check ionisation electrode and
connecting cable.
Reset burner.
Check free movement of the impel-
ler. Replace the fan unit if required.
Reset burner.
Restart the heat generator. If nec-
essary, reset the burner.
Check flue gas damper connection
at EM-EA1 (DIO) extension.
Check solenoid valve connection
at EM-EA1 (DIO) extension.