Viessmann VITODENS 300 Service Instructions Manual page 80

Troubleshooting
Fault codes
(cont.)
Display Const. Weath.-
fault comp.
code
E5 X X
E8 X X
E9 X X
EA X X
Eb X X
EC X X
80
System char- Cause
acteristics
Burner Internal fault
blocked
Burner control The ionisa-
unit fault tion current
lies outside
the permissi-
ble range
Burner control The ionisa-
unit fault tion current
lies outside
the permissi-
ble range
during cali-
bration
Burner control The ionisa-
unit fault tion current
lies outside
the permissi-
ble range
during cali-
bration
Burner control Heat draw-
unit fault off repeat-
edly too low
during cali-
bration
Burner control The ionisa-
unit fault tion current
lies outside
the permissi-
ble range
during cali-
bration
Remedy
Check the ionisa-
tion electrode and
leads. Check the
flue gas system
for soundness.
Press "E" and re-
place the control
unit, if required.
Check the ionisa-
tion electrode and
lead.
Press "E".
Check the ionisa-
tion electrode and
lead.
Press "E".
Check the ionisa-
tion electrode and
lead.
Press "E".
Initiate heat draw-
off and trigger
manual calibra-
tion (see
page 91).
Press "E".
Check the ionisa-
tion electrode and
lead.
Press "E".