Viessmann VITODENS 222-F Service Instructions Manual page 80

Troubleshooting
Corrective Action
80
(continued)
Vitodens 222-F B2TB 19 and 35 Service
Check flue gas temperature sensor
When exceeding the maximum permissible flue gas
temperature value, the flue gas temperature sensor locks
the appliance. Unlock the appliance by pressing reset
button R. after the vent system has cooled down.
1. Disconnect plug A from flue gas temperature
sensor B.
2. Check the sensor resistance and compare the actual
values with the curve in the chart.
3. Replace sensor in case of severe deviation.
Temperature sensors