Viessmann VITOCROSSAL 200 Service Instructions Manual page 46

Troubleshooting
Diagnosis
(cont.)
Fault Display
*1
code
F 16 None
F 4b F 4b
F 4c None
F 4d F 4d
F 4F F 4F
All fault codes are saved to the fault memory and the last 10 can be called up.
*1
46
System charac-
teristics
Burner control unit
in fault state
Could not find
parameter mem-
ory stick
Parameter mem-
ory stick matching
Incorrect pass-
word for parame-
ter memory stick
Type of parameter
memory stick
Cause
EMC fault
Parameter set
enabled, but
memory stick not
plugged into
burner control
unit; stick faulty
Parameters could
not be transferred
from the stick
Password entered
for stick invalid
Memory stick
does not match
burner control
unit
Measure
Have your system
tested for EMC
interference
Plug stick into
burner control unit;
replace stick
Replace stick or
burner control unit
Check password
and memory stick.
See installation
instructions, burner
components
Replace stick or
burner control unit
I Danger
Plug-in termi-
nals on the
burner control
unit 'live'.
Only replace
stick when the
power has
been isolated
from the
burner control
unit