Viessmann VITOLADENS333-F Service Instructions Manual page 77

Repairs
(cont.)
Checking the temperature limiter
If the burner control unit cannot be reset after a fault shutdown, although the
boiler water temperature is below approx. 90 °C, check the following:
1. Pull the leads from flue gas tem-
perature sensor A.
2. Check the sensor resistance and
compare it with the curve.
3. Replace the sensor in case of
severe deviation.
Troubleshooting
77