Outside Temperature Sensor - Viessmann VITODENS 111-W Installation And Service Instructions Manual

Troubleshooting
Repairs
(cont.)

Outside temperature sensor

X21 X7
X20
4 3 2 1
100
80
60
40
20
10
8
6
4
-15 -5 0
-10
Temperature in °C
44
10 20 30
1. Open the control unit casing. See
page 15.
2. Disconnect leads from outside tem-
perature sensor.
3. Check the sensor resistance and
compare it with the curve.
4. Replace the sensor in the case of
severe deviation.