External Demand; Venting Program; Fill Program; Screed Drying - Viessmann Vitodens 222-F Installation And Service Instructions For Contractors

Function description
Control functions
(cont.)
External blocking and fault message input
Input DE1
Input DE2
Input DE3
The effect on the internal circulation pump is selected
in coding address "3E" in the "General" group.

External demand

The "External demand" function is implemented via the
EA1 extension. There are 3 inputs available at the EA1
extension (DE1 to DE3).
External demand
Input DE1
Input DE2
Input DE3
The effect on the internal circulation pump is selected
in coding address "3F" in the "General" group.
The effect on the relevant heating circuit pump is
selected in coding address "d7" in the "Heating cir-
cuit" group.

Venting program

During the venting program, the circulation pump will
be alternately switched on and off for 30 s over a
period of 20 min.
The diverter valve alternates between heating and
DHW heating for a given time. The burner is switched
off during the venting program.

Fill program

In the delivered condition, the diverter valve is set to its
central position, enabling the system to be filled com-
pletely. After the control unit has been switched on, the
diverter valve no longer goes into its central position.
Afterwards, the diverter valve can be moved into the
central position via the fill function (see "Filling the
heating system"). In this position, the control unit can
be switched off and the system can be filled com-
pletely.

Screed drying

When activating screed drying, observe the informa-
tion provided by the screed manufacturer.
128
The effect on the relevant heating circuit pump is
selected in coding address "d6" in the "Heating cir-
cuit" group.
The function is selected via the following coding
addresses in the "General" group:
The set minimum boiler water temperature for external
demand is selected in coding address "9b" in the
"General" group.
Activating the venting program: See "Venting the heat-
ing system".
Filling with the control unit switched on
If the system is to be filled with the control unit
switched on, the diverter valve is moved to its central
position in the fill program, and the pump starts.
When the function is enabled, the burner shuts down.
The program automatically becomes inactive after
20 min.
When screed drying is activated, the heating circuit
pump for the heating circuit with mixer starts and the
flow temperature is maintained in accordance with the
selected profile. On completion (30 days), the heating
circuit with mixer is regulated automatically according
to the set parameters.
Code
3A:4
3b:4
3C:4
Code
3A:2
3b:2
3C:2