Viessmann Vitocal 242-S Installation And Service Instructions Manual page 74

Maintenance
Checking the sensors
Internal unit: Viessmann Pt500A (green ID label)
860
780
700
620
540
460
-20 20 60
Temperature in °C
Fig. 64
External unit: NTC 10 k
1000
100
10
1
0.1
-30 -20 -10
Temperature in °C
Fig. 65
74
(cont.)
100 140 180
(without ID)
Ω
0 10 20 30 40 50 60 70 80 90 100