Viessmann Vitocrossal 200 Service Instructions Manual page 44

Troubleshooting
Diagnosis
(cont.)
Fault code System character-
istics
37 The fan does not
reach its set speed
42 Burner control unit
remains in start up
position, no start in
spite of heat de-
mand
4E Burner control unit
fault
Scrolling Constant start at-
display: 1 tempt
2 3 4 5
7
Internal system fault
Internal system faults are created if a perfect program sequence can no longer
be guaranteed.
Fault code System character-
istics
01 and 02, Fault in the burner
04 to 15, control unit area
70 to 79,
7A, FF
FF Fault in the burner
control unit area
44
Cause Remedy
The fan is faulty; Check cable "100" or
cable "100" or "100a"; if required, re-
"100a" is faulty or place the cable or fan or
broken; the fan is remove foreign bodies.
blocked by a for-
eign body
Safety chain bro- Check jumper B2 (plug
ken fJ) of the safety chain
at the burner control
unit.
Internal fault Replace the burner con-
trol unit.
Cores "L1" and Check the power supply
"N" at the power and interchange the
supply terminals cores.
of the control unit
interchanged
Cause Remedy
Internal system Replace the burner con-
fault trol unit.
EEPROM Have your system
tested for EMC interfer-
ence.