Viessmann Vitoladens 300-C Service Instructions Manual page 70

Troubleshooting
Repairs
(cont.)
Checking the flue gas temperature sensor
The flue gas temperature sensor locks out the boiler when the permissible flue gas
temperature is exceeded. Reset interlock after flue gas system has cooled down by
pressing reset button "E".
70
1. Pull the lead from flue gas tempera-
ture sensor A.
2. Check the sensor resistance and
compare it with the curve.