Checking The Flue Gas Temperature Sensor - Viessmann VITOCROSSAL Service Instructions Manual

Checking the boiler water temperature sensor
20
10
8
6
4
2
1
0.8
0.6
0.4
10 30 50
Temperature in °C
Fig. 38 Sensor type: NTC 10 k

Checking the flue gas temperature sensor

Note
The flue gas temperature sensor is a dual sensor.
The flue gas temperature sensor locks out the boiler if
the permissible flue gas temperature is exceeded.
After the flue system has cooled down, press reset
button R to cancel the lock.
70 90 110
Ω
(cont.)
2. Measure the resistance of both sensors and com-
pare each with the curve.
3. In the event of severe deviation replace the sensor.
Maintenance
77