Control Functions - Viessmann Vitodens 300 Service Instructions Manual

Function description

Control functions

External operating mode changeover
The "External operating mode chan-
geover" function is connected via
external extension input aVD. With
coding address 91 you can select the
heating circuit to which the change-
over of operating mode should apply:
Coding
91:0
91:1
91:2
91:3
With coding address d5, you can
select in which direction the change-
over should be made for each heating
circuit:
Coding
d5:0
d5:1
You can select the duration of the
operating mode changeover with cod-
ing address F2.
Coding
F2:0
F2:1 to
F2:12
The changeover of operating mode
remains active as long as the contact
remains closed, but no less than the
default duration selected with coding
address F2.
102
Changeover of operating mode affects:
No changeover
Heating circuit without mixer (A1)
Heating circuit with mixer (M2)
Heating circuit without mixer and heating
circuit with mixer
Changeover of operating mode affects:
Changeover towards "Constantly reduced"
or "Constant standby mode" (subject to
the selected set value)
Changeover towards "Constant heating
mode"
Changeover of operating mode affects:
No changeover of operating mode
Duration of the operating mode change-
over 1 to 12 hours