Viessmann Vitoligno 300-P Service Instructions For Contractors page 88

Troubleshooting
Repairs
(cont.)
Check sensor
740
720
700
680
660
640
620
600
580
560
540
0 20
Flow temperature or
return temperature in ºC
Specification
Sensor type
Protection
Permiss. ambient
temperature
■ during operation 0 to + 100 °C
■ during storage
and transport
Radio clock receiver, part no. 7450 563
The radio clock receiver sets the time at the control unit and any remote control that
may be connected, fully automatically.
88
40 60 80 100
Viessmann Ni500
IP 32
−20 to + 70 °C
1. Pull plug ?.
2. Check the sensor resistance at the
plug.
3. Compare the measurement with the
actual temperature displayed (for
scanning, see chapter "Tempera-
tures, boiler coding card and brief
scans").
Check the installation and, in the
case of severe deviation, replace the
sensor.