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Vitodens 100-W, B1HA series & B1KA Combi Installation/Service
Boiler Connection
(continued)
Check fixed high limit
Check flue gas temperature sensor
If the burner control unit cannot be reset after a fault
shutdown (
F2
), even though the boiler water temperature
is below approx. 203°F (95°C), check the fixed high limit.
1. Pull the leads from fixed high limit
A
.
2. Check the continuity of the fixed high limit with
a
multimeter.
3. Remove faulty fixed high limit.
4. Coat the replacement fixed high limit with heat
conducting paste and install.
5. To reset, refer to page 76.
1. Pull the leads from flue gas temperature sensor
A
.
2. Check the sensor resistance and compare it with the
curve.
3. Replace the sensor in case of severe deviation.
Resistance in K
Temperature
Troubleshooting
