Viessmann VITOCROSSAL 200 Service Instructions Manual page 41

Diagnosis
(cont.)
Fault code System characteris-
tics
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
25 No flame signal after
the safety time; the
ionisation flame mon-
itor reports no flame
signal
Cause
Ionisation elec-
trode incorrectly
adjusted
Ignition electrodes
incorrectly adjus-
ted
Insulation body of
ignition electrodes
cracked
Incorrect gas type
selected
Gas train does not
open
Combustion char-
acteristics not
ideal
Incorrect parame-
ter set selected
285 kW burner for
open flue opera-
tion
Troubleshooting
Measures
Adjust ionisation elec-
trode (see page 24).
Adjust ignition electrodes
(see page 24).
Replace the ignition elec-
trodes
Adjust gas type (see
page 9).
Check the gas train and
replace if required
Adjust burner (see from
page 14).
Adjust the parameter set
(see page 36 to 37).
Adjust burner settings
(see page 46).
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