Vaillant auroCOMPACT VSC S/4 Series Installation And Maintenance Instructions Manual page 31

Note
When starting up the product or after switching
on the power supply, this pump setting does
not take effect until after the burner has run for
the first time.
Setting for KfW
▶
Set D.014 to 7 (= fixed (Δp Limit)).
Conditions: The hydraulics in the heating system or the heating sys-
tem itself is suitable for this type of pump operation.
–
The pump is only operated at this pump speed.
The hydraulic power of the pump for transferring
the heat output is limited.
◁
The pump is permanently set to a lower pump speed
with a maximum feed head of 200 mbar.
Note
If the heating system is not suitable for this
type of pump operation, this can lead to in-
sufficient supply to the product and to safety
shutdowns.
▶
Make sure that there is a guaranteed minimum flow of
heating water via the heating system to transfer the heat
output.
Note
The bypass valve remains inoperative as
the pump speed is not sufficient to open
it (provided the factory settings remain
unchanged).
Note
If the "Pump speed target value = fixed (Δp
Limit)" pump operating mode is selected, the
product's maximum heat output is automatic-
ally no longer available. The relevant nominal
output is adapted to the hydraulic potential of
this pump speed at the factory.
Characteristic line for proKlima (25 kW)
Changes must be made during the installation for the proK-
lima or KfW label.
Setting for proKlima
Note
On 25 kW units, the bypass must not be replaced
with the proKlima plug.
▶
Set D.014 to 6 (= auto (Δp limit)).
▶
Set D.122 to 200 or a lower value (= maximum hydraulic
pressure difference ≤ 200 mbar).
◁
The hydraulic pressure difference with respect to the
heating system is limited to the set value (see dia-
gram).
0020181589_04 auroCOMPACT Installation and maintenance instructions
Adapting the unit to the heating installation 8
Setting for KfW
▶
Set D.014 to 7 (= fixed (Δp Limit)).
Conditions: The hydraulics in the heating system or the heating sys-
tem itself is suitable for this type of pump operation.
–
The pump is only operated at this pump speed.
The hydraulic power of the pump for transferring
the heat output is limited.
◁
The pump is permanently set to a lower pump speed
with a maximum feed head of 200 mbar.
▶
Make sure that there is a guaranteed minimum flow of
heating water via the heating system to transfer the heat
output.
8.8.3 Setting the bypass valve
Applicability: Austria
The pressure can be adjusted in a range between 17 kPa
(0,17 bar) and 35 kPa (0,35 bar). The default value is ap-
prox. 30 kPa (0,30 bar) (mid-position).
The pressure changes by approximately 1 kPa (0,01 mbar)
each time the adjusting screw is rotated. The pressure is
increased by turning clockwise and decreased by turning
anti-clockwise.
Note
When starting up the product or after switching
on the power supply, this pump setting does
not take effect until after the burner has run for
the first time.
Note
If the heating system is not suitable for this
type of pump operation, this can lead to in-
sufficient supply to the product and to safety
shutdowns.
Note
The bypass valve remains inoperative as
the pump speed is not sufficient to open
it (provided the factory settings remain
unchanged).
Note
If the "Pump speed target value = fixed (Δp
Limit)" pump operating mode is selected, the
product's maximum heat output is automatic-
ally no longer available. The relevant nominal
output is adapted to the hydraulic potential of
this pump speed at the factory.
Caution.
Risk of material damage caused by incor-
rect setting of the high-efficiency pump
If the pressure at the bypass valve is in-
creased (by turning it clockwise) and the
pump output is set to less than 100%, the
product may not operate correctly.
31