98
100
10
-20 -10 0 10 20 30
Temperature in °C
6
8
20
40
60
80
200
Resistance
in kΩ
Fig. 57
Sensor type: NTC 10 k
Ω
1.
Pull plug "X3" from the control unit.
2.
Test the resistance of the outside temperature sen-
sor across terminals "X3.1" and "X3.2" on the dis-
connected plug and compare it with the curve.
3.
Where actual values deviate severely from the
curve values, disconnect the wires at the sensor
and repeat the test on the sensor itself.
4.
Depending on the result, replace the lead or the
outside temperature sensor.
Checking the boiler water temperature sensor, cylinder temperature sensor or flow temperature
sensor of low loss header
X3
5
A
Fig. 58
Troubleshooting
Maintenance
(cont.)
5778741
Diagnosis