External Extension H - Viessmann VITODENS 200-W Service Instructions Manual

Function description
Extensions for external connections . . .

External extension H1

The external extension is connected
to the boiler control unit via the KM
BUS. The following functions can be
controlled or processed simulta-
neously via the extension:
A ON/OFF switch (on site)
sÖ Heating circuit pump for the
heating circuit without mixer
sA Cylinder primary pump
sK DHW circulation pump (only for
weather-compensated opera-
tion)
fÖ Power supply
gÖ Central fault message
96
(cont.)
aVD External blocking
(terminals 2 - 3)
External demand
(terminals 1 - 2)
External heating program
changeover (terminals 1 - 2)
(only for weather-compen-
sated operation)
The allocation of the function
"External heating program
changeover" is set via coding
address "91".
aVF External set value 0 to 10 V
aVG KM BUS