Viessmann VITODENS 200-W WB2B 105, Start-Up/Service Instructions

Page: 56 / 80

Troubleshooting
56
Diagnostics
(continued)
Fault codes
(continued)
Fault code on display System behavior
*1
Cause Corrective action
40 Mixing valve closes Heating circuit with mixing
valve supply temperature
sensor shorted out Check the supply
temperature sensor
(see page 60).
48 Mixing valve closes Heating circuit with mixing
valve supply temperature
sensor cable broken Check the supply
temperature sensor
(see page 60).
50 No DHW heating Tank temperature
sensor shorted out Check the sensor
(see page 60).
58 No DHW heating Tank temperature sensor
cable broken Check the sensor
(see page 60).
92 Control mode Collector temperature sensor
shorted out; connects to the
Vitosolic at S1 Check the sensor at the
Vitosolic solar control.
93 Control mode Collector temperature sensor
shorted out; connects to the
Vitosolic at S3 Check the sensor at the
Vitosolic solar control.
94 Control mode Collector temperature sensor
shorted out; connects to the
Vitosolic at S2 Check the sensor at the
Vitosolic solar control.
9A Control mode Collector temperature sensor
cable broken; connects to the
Vitosolic at S1 Check the sensor at the
Vitosolic solar control.
9b Control mode Tank temperature sensor
cable broken; connects to the
Vitosolic at S3 Check the sensor at the
Vitosolic solar control.
9C Control mode Tank temperature sensor
cable broken; connects to the
Vitosolic at S2 Check the sensor at the
Vitosolic solar control.
9F Control mode Solar control unit fault;
displayed if a fault without
fault code occurs at the solar
control unit Check the solar control unit
(see solar control service
instructions).
A7 Control mode (stays in
factory default setting) Faulty programming unit Replace the programming
unit.
b0 Burner blocked Flue gas temperature sensor
shorted out Check flue gas temperature
sensor (see page 61).
b1 Control mode (stays in
factory default setting) Communication fault;
programming unit (internal) Check connections and
replace programming unit if
required.
b4 Regulates as if the outdoor
temperature was 0°C Internal fault Replace the control unit.
b5 Control mode
(factory default setting) Internal fault Replace the control unit.
b7 Burner blocked Boiler coding card missing,
faulty or incorrect boiler
coding card Plug in boiler coding card or
replace if faulty.
b8 Burner blocked Flue gas temperature sensor
cable broken Check flue gas temperature
sensor (see page 61).
5
4
4
3
2
0
7
v
1
.5