Viessmann Vitovalor PT2 Installation And Service Instructions For Contractors page 130

Troubleshooting
Fault messages on the gas condensing...
Control unit System characteristics
message
F.448 Burner in a fault state
F.449 Burner in a fault state
F.450 Burner in a fault state
F.451 Burner in a fault state
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 in a fault state
F.462 Burner in a fault state
130
(cont.)
Cause
Deviation, ionisation cur-
rent signal
Error in scheduled pro-
gram run monitoring
Error in scheduled pro-
gram run monitoring
Error in scheduled pro-
gram run monitoring
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 connection at
EM-EA1 (electronics mod-
ule DIO) extension input
preventing burner start.
LPG safety valve (sole-
noid valve) at EM-EA1
(electronics module DIO)
extension does not open.
Measures
Check ionisation electrode.
Reset device.
Reset device.
Reset device.
Reset device.
Reset device.
Reset device.
Flash the correct software version
for the burner control unit.
Reset device.
Reset device.
Check impeller for ease of opera-
tion. Replace fan unit if necessary.
Reset device.
Restart heat generator. Unlock de-
vice is necessary.
Check flue gas damper connection
at EM-EA1 (electronics module
DIO) extension.
Reset device.
Check solenoid valve connection
at EM-EA1 (electronics module
DIO) extension.
Reset device.