Viessmann FB2B Installation And Service Instructions Manual page 136

Function description
Control functions
Heating program changeover
No heating program changeover
Duration of the heating program changeover 1 to 12 hours
The heating program changeover stays
enabled for as long as the contact
remains closed, but at least as long as
the duration selected in coding address
"F2".
External blocking
The "External blocking" and "External
blocking and fault message input" func-
tions are connected via extension EA1.
There are 3 inputs available at extension
EA1 (DE1 to DE3).
External blocking
Input DE1
Input DE2
Input DE3
External blocking and fault message input
Input DE1
Input DE2
Input DE3
The effect on the internal circulation
pump is selected with code 3E.
External demand
The "External demand" function is con-
nected via extension EA1. There are 3
inputs available at extension EA1 (DE1
to DE3).
136
(cont.)
The function is selected via the following
codes:
The effect on the relevant heating circuit
pump is selected with code d6.
The function is selected via the following
codes:
Code
F2:0
F2:1 to
F2:12
Code
3A:3
3b:3
3C:3
Code
3A:4
3b:4
3C:4