Control Functions; External Operating Program Changeover - Viessmann VITOCROSSAL Service Instructions Manual

Function description
External extension (accessories)
Effect of the "External blocking" function on the
circulation pumps
The effect on the relevant heating circuit pump is
selected with code d6.
The effect on a circulation pump for cylinder heating is
selected with code 5E.
Effect of the "External demand" function on the
circulation pumps
The effect on the relevant heating circuit pump is
selected with code d7.
The effect on a circulation pump for cylinder heating is
selected with code 5F.
DHW circulation pump runtime for brief operation
The runtime is set in code 3d.
Analogue input 0 - 10 V
The 0 to 10 V hook-up provides an additional set boiler
water temperature:

Control functions

External operating program changeover

The "External operating program changeover" function
is implemented via the EA1 extension. There are 3
inputs available at the EA1 extension (DE1 to DE3).
Operating program changeover
Input DE1
Input DE2
Input DE3
The heating program changeover function for the
respective heating circuit is assigned at the boiler con-
trol unit via code d8:
Operating program changeover
Changeover via input DE1
Changeover via input DE2
Changeover via input DE3
You can select which direction the operating program
changeover takes in coding address "d5":
Operating program changeover
Changeover towards "Permanently reduced" or "Permanent standby mode" (ac-
cording to the selected set value)
Changeover towards "Continuous heating mode"
86
(cont.)
≙
0 - 1 V "No specification for set boiler water temper-
ature"
≙
1 V Set value 10 °C
≙
10 V Set value 100 °C
Output
aBJ
One of the following functions can be connected to
output :
aBJ
■ Feed pump to substation
DHW circulation pump
■
Fault message facility
■
Note on DHW circulation pumps
Connect DHW circulation pumps with standalone func-
tions directly to the 230 V ∼ supply.
Function assignment
The function of output
control unit via code 36.
The function is selected via the following codes:
aBJ is selected at the boiler
Code
3A:1
3b:1
3C:1
Code
d8:1
d8:2
d8:3
Code
d5:0
d5:1