High Limit Safety Cut-Out - Viessmann VITOLIGNO 250-S Operating Instructions Manual

Steps to take in the event of overheating

High limit safety cut-out

Fig. 12
Triggering the function
If the boiler water temperature exceeds 95 °C the high
limit safety cut-out responds.
Cancelling the function
Note
The high limit safety cut-out can only be reset
(unlocked) once the boiler water temperature has
reached approx. 70 °C.
After each triggering of the high limit safety cut-out,
check that the thermally activated safety valve is reset.
1. Unscrew protective cap
2. Press the green button on the high limit safety cut-
out.
A faint "click" will be audible, the high limit safety
cut-out is reset.
3. Acknowledge the excess temperature on the pro-
gramming unit of the control unit with
4. Refit protective cap
A
A .
.
d
over the green button.
(cont.)
Reset button of the high limit safety cut-out is loca-
A
ted on the front of the boiler.
Note
The high limit safety cut-out can only be reset man-
ually.
Start-up/shutdown
19