Viessmann KWT BW 301.B090, Installation And Service Instructions Manual

Page: 41 / 100

41
Plug sXS
Terminals Function Explanation
222.3
222.4 Control of external heat generators
with 2 high limit safety cut-outs (max.
70 °C) for the heat pump and to switch
off the secondary pump Floating contact
Note
■
The switching contact is a floating N/O contact that
is closed when a heat demand is issued.
■
Never route low voltage via this contact. For that, fit
a relay on-site.
■
The boiler water temperature sensor in the external
heat generator (plug F20) must capture the average
temperature of the external heat generator.
Connection values (contact rating):
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
Connect the high limit safety cut-out on site:
■
In series with the secondary pump (terminal 211.2
on main PCB), see separate "Connection and wiring
diagram" sheet 20.
■
In series for controlling external heat generators, see
separate "Connection and wiring diagram"
sheet 170, sheet 171, sheet 172.
Plug
sXF
Terminals Function Explanation
224.4
r
2.
Instantaneous heating water heater
switching, stage 2 Connection values
■
Output: 10 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
Connection, see separate "Connection and wiring dia-
gram" sheet 110.
224.6
M
■
Cylinder primary pump (DHW side)
■
2-way shut-off valve
Connect cylinder primary pump and 2-way shut-off
valve in parallel.
Connection values
■
Output: 130 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
Connection, see separate "Connection and wiring dia-
gram" sheet 150.
Use contactor if required; see separate "Connection
and wiring diagram" sheet 151, sheet 152.
224.7 Circulation pump for DHW reheating Connection values
■
Output: 100 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
Connection, see separate "Connection and wiring dia-
gram" sheet 170.
Use contactor if required; see separate "Connection
and wiring diagram" sheet 171, sheet 172.
Installation sequence
Overview of electrical connections
(cont.)
5549 984 GB
Installation