Viessmann Vitodens 300 - Page 84

Displayed
fault c ode
Con-
st.
Weat -
her-
com-
p.
System
character-
istics
Cause Remedy
F8 X X Burner in
fault state
Fuel valve
closes too late
Check gas combi -
nation valve. Check
both control paths.
Press E.
F9 X X Burner in
fault state
Fan speed too
low at burner
start
Check the fan,
check the fan
cables and supply,
check the fan co n-
trol.
Press E.
FA X X Burner in
fault state
Fanstopnot
achieved
Check the fan,
check the fan
cables, check the
fan control.
Press E.
Fd X X Burner
blocked
Burner contr ol
unit fault
Check the ignition
electrodes and
leads. Check
whether a strong
interference (EMC)
field exists near the
equipment.
Press E.
If the fault is not
removed, re place
the control unit.
FE X X Burner
blocked
Strong inter-
ference (EMC)
field nearby ;
alternatively
boiler co ding
card or main
PCB faulty
Remove EMC i nter-
ference. If the
equipment will not
restart, check the
boiler coding card
and r eplace, or
replace the control
unit.
Checking and acknowledging faults (cont.)
84
Troubleshooting
5692 537 GB