Installation
42
Connection of external controls (VD2/VD2A only)
(continued)
Modulating boilers – operation with external modulation controller
(continued)
Settings on the control unit
The settings for the fixed high limit and
the other settings are dependent on the
safety equipment installed in
accordance with applicable codes.
Non-condensing boiler
(VD2/VD2A)
°
C /
°
F
Condensing boiler
(CT3)
°
C /
°
F
Condensing boiler
(CM2)
°
C /
°
F
Fixed high limit
110 / 230
99 / 210
99 / 210
99 / 210
Adjustable high limit
100 / 212
95 / 203
95 / 203
95 / 203
Coding for the electronic maximum
temperature limiter of Vitotronic 100;
set code 06 to the temperature as
shown or less
93 / 200
87 / 188
87 / 188
88 / 190
Single-boiler systems:
Coding ”01: 1”
(factory setting)
When a building automation system is
connected, only the connections on
plug
aVD
are required. The DHW tank
control unit is activated when the DHW
tank temperature sensor is connected.
The boiler water temperature must be
set to the minimum value.
Multi-boiler systems:
Set coding ”01: 3”
When a building automation
system is connected, the
connections on plugs
aVD
and
aVH
are required.
The DHW tank temperature and
the load-dependent cascade control
must be controlled through the
external building automation
system.
5285
941
-
0
1
The boiler activation contact is
essential on multi-boiler systems.
The contact on the lead boiler
MUST be constantly closed.
CAUTION