Viessmann Vitocrossal 300 Service Instructions Manual page 36

Troubleshooting
Diagnosis
(cont.)
Fault code Shown on
*1
display
F 54 F 54
F 55 F 55
Internal system faults
Internal system faults occur if a flawless program
sequence can no longer be guaranteed.
Fault code Shown on
*1
display
01, 02, 05 to 01, 02, 05 to
0d, 0F, 14, 15, 0d, 0F, 14,
17, 1A to 1c, 15, 17, 1A to
1E, 45, 47, Ac, 1c, 1E, 45,
b0 47, Ac, b0
F 0E, F F 0E, F
1d 1d
03 03
All fault codes are saved to the fault memory and the last 10 can be called up.
*1
36
System characteristics
PWM values incorrect
Parameter memory stick
fault
System characteristics
Fault in burner control
unit area
Fault in burner control
unit area
Fault in burner control
unit area
Fault in burner control
unit
Cause of fault
EEPROM of memory
stick modified or deleted;
memory stick faulty
Memory stick faulty
Cause of fault
Internal system fault and
EMC
EEPROM or internal sys-
tem fault; EMC fault
Processor crashed
Excess temperature
( 60 C)
> º
Measure
Replace memory stick.
I
Danger
Plug-in terminals on
the burner control
unit are live.
Only replace memory
stick when burner
control unit has been
isolated from power
supply.
Replace memory stick.
I
Danger
Plug-in terminals on
the burner control
unit are live.
Only replace memory
stick when burner
control unit has been
isolated from power
supply.
Steps to take
Replace burner control
unit.
Measure against EMC:
Try connecting to another
phase
Have your system tested
for EMC interference; re-
place the burner control
unit.
Have your system tested
for EMC interference; re-
place the burner control
unit.
Check ambient tempera-
ture.