Viessmann VITOCAL 222-S Installation And Service Instructions Manual page 75

Checking the sensors
External unit: NTC 50 k
1000
100
10
1
0.1
-30 -20 -10 0
Temperature in °C
Fig. 66
Checking fuses
Fuse location: See from page 33.
Fuse F1 is located on the mains terminal of the heat
■
pump control unit.
■ Fuse F3 is located on the main PCB.
■ Fuse F101 is located on the AVI PCB.
Fuses F1 and F3:
6.3 A (slow, H), 250 V~
■
Max. power loss 2.5 W
■
≤
Danger
Removing the fuse does not switch the power
circuit to zero volt. Contact with 'live' compo-
nents can lead to serious injury from electric cur-
rent.
Before working on the equipment, always
ensure that the power circuit is also at zero
volt.
(cont.)
(without ID)
Ω
10 20 30 40 50 60 70 80 90
Fuse F101:
■ 1.0 A (slow, L)
■ Max. power loss 2.5 W
≤
Maintenance
100
75