Viessmann VITODENS 050-W Installation And Service Instructions Manual page 59

Repairs
(cont.)
Checking the temperature limiter
3. In the case of severe deviation,
drain the boiler on the heating
water side and replace the sensor.
If the burner control unit cannot be
reset after a fault shutdown, although
the boiler water temperature is below
approx. 95 °C, check the temperature
A
limiter.
1. Disconnect the leads from tempera-
ture limiter A.
2. Check the continuity of the temper-
ature limiter with a multimeter.
3. Remove faulty temperature limiter.
4. Install a new temperature limiter.
5. Reset by pressing "Reset" on the
control unit (see page 54).
Troubleshooting
Danger
The boiler water tempera-
ture sensor is directly
immersed in the heating
water (risk of scalding).
Drain the boiler before
replacing the sensor.
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