Viessmann VITOTRONIC 100 GC1 Installation And Service Instructions Manual page 127

Wiring Diagrams
Low-voltage motherboard (continued)
§
Boiler temperature sensor
%
Tank temperature sensor
(accessory)
aG
Flue gas temperature sensor
(accessory)
(continued)
aJA Temperature sensor T1
aJB Temperature sensor T2
aVD Connection of external
equipment
aVG KM BUS participant (accessory)
aVH Connection of external
equipment
LON Connecting cable for data
transfer between the control
units
Additional information
S3 Override switch "S"
V1 Fault indicator (red)
V2 Operating status indicator (green)
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