Viessmann Vitocal 300-G BW, Installation And Service Instructions Manual

Page: 171 / 216

171
Function Explanation Connection
Brine pressure limiter, frost
stat (fault message from
AC-Box) If both limiters are installed wire in ser-
ies:
■ Closed = safety chain has continuity
■ Open = safety chain break; appliance
not operational
■ Either jumper or limiter(s) must be
connected
■ Breaking capacity 230 V~, 0,5 A
■ Delivered condition: No jumper fitted
1X3.9
1X3.8
External blocking / mixer
CLOSE Connect zero volt contact on site:
■ Closed = blocking enabled
■ Open = no blocking
■ Breaking capacity 230 V, 0,1 A 1X3.2
1X3.14
or to external
extension
H1
Power-OFF Connect zero volt contact on site:
■ Closed = no blocking
■ Open = blocking enabled
■ Breaking capacity 230 V, 0,5 A
■ Delivered condition: Jumper fitted 1X3.7
1X3.6
Flow switch Connect zero volt contact on site:
■ Closed = appliance operational
■ Open = appliance operational, fault
message via display
■ Breaking capacity 230 V, 0,1 A
■ Delivered condition: Jumper fitted
■ Contact not integrated into the safety
chain
1X3.3
1X3.4
Connection and wiring diagrams
PCB 1: Message and safety components
(cont.)
5368 522 UAE
Service