41
Displayed fault
code
System characteristics
Cause
Measures
F F9
No feedback from fan
External fan power supply
not connected, faulty or
defective. If voltage is
present at connected plug
"
a-Ö
" and the fan does
not start up when plug
"
a-Ö
A" is disconnected,
there is a fault with the
fan. Cable "
a-Ö
A" faulty or
broken.
Relay in the terminal box
does not switch.
Fan blocked (possibly by
foreign bodies).
Check cable"
a-Ö
A" and external
power supply. Replace cable or
fan. Remove foreign bodies.
F FA
Fan runs without demand;
burner control unit in a fault
state.
Fan does not reach idle
state, cable "
a-Ö
A" faulty,
fan faulty, burner control
unit faulty
Wind influence on fan; check flue
outlet and fan. Replace cable
"
a-Ö
A". Replace fan. Replace
burner control unit.
F 80
Burner control unit in a fault
state; system cooling down;
burner control unit locked out.
Short circ., boiler temp
sensor
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
F 81
Burner control unit in a fault
state
Sensor drift, boiler water
temperature sensor
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
F 82
Burner control unit in a fault
state; system cooling down;
burner control unit locked out.
Short circ., flue gas temp
sensor
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
F 83
Burner control unit in a fault
state
Sensor drift, flue gas tem-
perature sensor
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
F 88
Burner control unit in a fault
state
Lead break, boiler water
temperature sensor
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
F 89
Burner control unit in a fault
state
Lead break, flue gas tem-
perature sensor
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
F E3
Burner control unit in a fault
state
Safety equipment has re-
sponded.
Check safety equipment on
STB/STB at plug
aBÖ
of the
Vitotronic.
F EB
Burner locked out
Burner not enabled via ex-
ternal contact.
Check components connected to
TR/TR EIN at plug
aBÖ
of the
Vitotronic.
F EC
Burner control unit in a fault
state
Internal error in feedback
from safety relay.
Reset the burner control unit. Re-
place burner control unit if re-
quired.
F ED
Burner control unit in a fault
state
Internal error in feedback
from ignition relay.
Reset the burner control unit. Re-
place burner control unit if re-
quired.
Troubleshooting
Fault codes
(cont.)
5816717
Diagnosis
