Viessmann VITOCAL 300-A Installation And Service Instructions Manual page 90

Installation sequence
Electrical connections in the control unit
External demand, external mixer "OPEN", operating mode changeover
A Terminals on PCB 1
B Zero volt N/O contact outside the
control unit (on site)
Breaking capacity 230 V~; 0.1 A
Required parameter (code to be entered by "Contractor": 5243)
Function
External demand
External mixer "OPEN"
External operating mode changeover
External blocking, external mixer "CLOSE"
A Terminals on PCB 1
B Zero volt N/O contact
Breaking capacity 230 V~; 0.1 A
90
(cont.)
Parameter (ID) Ó Setting
No parameters required; the set flow
temperature for external demand can
be defaulted (see page 156).
"System definition"
"Ext.demand/Miopen" (7014) Ó "0"
&
to "7" (see page 137). Observe para-
meter "Set flow ex. demand" (see
page 156).
"System definition"
"Op mode change HC" (7011) Ó
&
"0" to "10" (see page 135)
"Op mode change eff." (7012) Ó
&
"0" to "3" (see page 136)
"Op mode change time" (7013) Ó
&
"0" to "12" (see page 137)