Viessmann VITOCAL 300-G Installation And Service Instructions For Contractors page 27

Electrical connection
Plug
sYA
Terminals Function
211.2 Additional secondary pump to in-
crease residual head
Installation outside the heat pump
■
in the secondary circuit flow
No switching via PWM signal from
■
the heat pump control unit
Note
The factory-fitted secondary pump
■
is connected to the EEV PCB: See
chapter "Overview of electrical com-
ponents".
The factory-fitted secondary pump
■
must be operated at a constant
100 % speed ("Rated output sec-
ondary pump (PWM) 7343" at
"100").
211.5 Cooling control via NC-Box
NC NC function (natural cooling)
Plug
sYS
Terminals Function
212.1 Control of active cooling function
AC
212.2 Heating circuit pump for heating cir-
cuit without mixer A1/HC1
A1
(cont.)
Explanation
In systems without a buffer cylinder, no other heating
■
circuit pump is required: See connection 212.2.
Connect a temperature limiter in series to restrict the
■
maximum temperature of underfloor heating circuit (if
installed).
Supply values
Output: 140 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
■
Connection values
Output: 10 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
■
Explanation
Components for AC cooling
Supply values
Output: 10 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
■
This pump is connected in addition to the secondary
■
pump if a heating water buffer cylinder is installed.
Connect a temperature limiter in series to restrict the
■
maximum temperature of underfloor heating circuit (if
installed).
Note
In systems without heating water buffer cylinder the
temperature limiter is connected to X3.2/X3.14 at the
luster terminals: See chapter "Temperature limiter to re-
strict the maximum temperature of underfloor heating".
Supply values
Output: 100 W
■
Voltage: 230 V~
■
Max. switching current: 4(2) A
■
Installation sequence
27