Viessmann VITODENS 200-W Service Instructions Manual page 94

Troubleshooting
Fault codes
(cont.)
Dis- Const.
played
fault
code
48
4C
50 X
51 X
58 X
59 X
90 X
91 X
92 X
94
Weath.- System char-
comp. acteristics
X Mixer closes
X Mixer closes
X No DHW heat-
ing
X No DHW heat-
ing
X No DHW heat-
ing
X No DHW heat-
ing
X Control mode
X Control mode
X No DHW heat-
ing
Cause Measures
Lead break, Check flow temper-
flow tempera- ature sensor
ture sensor,
heating circuit
2 (with mixer)
Lead break, Check flow temper-
flow tempera- ature sensor
ture sensor,
heating circuit
3 (with mixer)
Short circuit, Check the cylinder
cylinder tem- temperature sen-
perature sen- sor (see page 106)
sor or comfort or comfort sensor
sensor (see page 108)
Short circuit, Check sensor (see
outlet temper- page 108)
ature sensor
Lead break, Check the cylinder
cylinder tem- temperature sen-
perature sen- sor (see page 106)
sor or comfort or comfort sensor
sensor (see page 108)
Lead break, Check sensor (see
outlet temper- page 108)
ature sensor
Check sensor /
Short circuit,
temperature
on the solar control
sensor / module
Short circuit, Check sensor aÖ
temperature
on the solar control
sensor aÖ module.
Short circuit, Check temperature
collector tem- sensor & on the
perature sen- solar control mod-
sor
ule or the Vitosolic
sensor