Viessmann Vitocrossal 200 Series Service Instructions Manual page 44

Troubleshooting
Fault codes
(cont.)
Fault code dis- System characteristics
played
F F8 Flame tears off during opera-
tion.
F F8 Flame tears off during opera-
tion.
F F8 Flame tears off during modu-
lation (burner output increa-
ses).
F F9 Fan not running; fan speed
not reached.
F F9 Status duration too long, fan
ramp-up
F F9 Fan speed deviation
F F9 No feedback from fan
F FA Fan runs without demand;
burner control unit in a fault
state.
F 80 Burner control unit in a fault
state; system cooling down;
burner control unit locked out.
F 81 Burner control unit in a fault
state
F 82 Burner control unit in a fault
state; system cooling down;
burner control unit locked out.
F 83 Burner control unit in a fault
state
F 88 Burner control unit in a fault
state
F 89 Burner control unit in a fault
state
F E3 Burner control unit in a fault
state
44
Cause
Burner gauze assembly
contaminated or faulty
Combustion characteris-
tics not ideal
Combustion characteris-
tics not ideal
Air pressure switch adjus-
ted incorrectly.
Fan faulty; cables are faul-
ty or broken
Internal fault; fan cannot
reach its set value.
Fan faulty, cable " A"
a-Ö
faulty or broken
Fan faulty, external fan
power supply not connec-
ted or faulty, cable " A"
a-Ö
faulty or broken, fan
blocked (poss. by foreign
bodies)
Fan does not reach idle
state, cable " A" faulty,
a-Ö
fan faulty, burner control
unit faulty
Short circuit, boiler water
temperature sensor
Sensor drift, boiler water
temperature sensor
Short circuit, flue gas tem-
perature sensor
Sensor drift, flue gas tem-
perature sensor
Lead break, boiler water
temperature sensor
Lead break, flue gas tem-
perature sensor
Safety equipment has re-
sponded.
Measures
Clean the burner gauze assembly
with compressed air. Replace the
burner gauze assembly if it is dam-
aged.
Adjust burner (see page 16).
Adjust burner (see page 16).
Adjust air pressure switch (see
page 50).
Check cables. Replace fan if re-
quired.
Replace fan or burner control unit.
Check cable. Replace cable
" A" or fan if necessary.
a-Ö
Check cable" A" and external
a-Ö
power supply. Replace cable or
fan. Remove foreign bodies.
Wind influence on fan; check flue
outlet and fan. Replace cable
" A". Replace fan. Replace
a-Ö
burner control unit.
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
Check connecting cable and boiler
water temperature sensor 3A/3B
(dual sensor). Replace sensor if re-
quired.
Check connecting cable and flue
gas temperature sensor 15A/15B
(dual sensor). Replace sensor if re-
quired.
Check safety equipment on
STB/STB at plug of the
aBÖ
Vitotronic.