Viessmann VITODENS 300 WB3A, Service Instructions Manual

Page: 118 / 148

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 Changeover of operating mode affects:
91:0 No changeover
91:1 Heating circuit without mixer (A1)
91:2 Heating circuit with mixer (M2)
91:3 Heating circuit without mixer and heating
circuit with mixer
With coding address d5, you can
select in which direction the change-
over should be made for each heating
circuit:
Coding Changeover of operating mode affects:
d5:0 Changeover towards "Constantly reduced"
or "Constant standby mode" (subject to
the selected set value)
d5:1 Changeover towards "Constant heating
mode"
You can select the duration of the
operating mode changeover with cod-
ing address F2.
Coding Changeover of operating mode affects:
F2:0 No changeover of operating mode
F2:1 to
F2:12 Duration of the operating mode change-
over 1 to 12 hours
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.
Control functions
102
Function description
56
92
550
GB