Viessmann Vitodens 100 Series Installation And Service Instructions Manual page 30

Installation sequence
Electrical connections
Connection OpenTherm accessories
X7
1 2 3
B
1 2 3 4
OT
A
A OpenTherm accessories
B Terminals on the control unit
Connecting system to equipotential bonding of the building
Danger
The absence of system compo-
nent earthing can lead to seri-
ous injury from electric current if
an electrical fault occurs.
30
(cont.)
4
Note
Observe parameter "P07", see
page 58.
Recommended connecting cable
■ 2-core cable for low voltage
The appliance and pipework
(especially the gas line) must be
connected to the equipotential
bonding of the building.