88
Viessmann NTC 10 kΩ (marked blue)
Outside temperature sensor
100
10
-20 -10 0 10 20 30
Temperature in °C
6
8
20
40
60
80
200
Resistance in k
Ω
Other sensors
10
1
10 30 50 70 90 110
Temperature in °C
0.4
0.6
0.8
2
4
6
8
20
Resistance in k
Ω
Viessmann Pt500A (marked green)
460
20
540
100
Resistance in
Temperature in °C
60
140 180
620
700
780
860
-20
Checking MCB/fuses
For fuse locations, see page 34.
■ Fuse F1 is located on the cross con-
nect PCB.
■ Fuse F3 is located on the main PCB.
Fuses F1 and F3:
■ 6.3 A (slow), 250 V~
■ Max. power loss ≤ 2.5 W
Troubleshooting
Repairs
(cont.)
5546 267 GB
