Viessmann VITOLIGNO 200-S Technical Manual page 64

Installation accessories
Dimensions Manifold with heating circuit connection
R ¾ and R 1
a 135
b 535
c 784
d G 1¼
Determining the required nominal diameter
5.0
2.5
2.0
1.5
1.0
0.5
0.2
0.1
Mixer control characteristics
A Divicon with mixer-3
The operating ranges marked B to D provide optimum control
characteristics with the Divicon mixer:
B Divicon with mixer-3 (R ¾)
Application range: 0 to 1.0 m
5
Example:
Heating circuit for radiators with an heating output of ² = 11.6 kW
Heating system temperature 75/60 °C (ΔT = 15 K)
c Specific thermal capacity
µ Mass flow rate
² Heating output
´ Flow rate
Circulation pump curves and pressure drop on the heating water
side
The residual pump head results from the differential between the
selected pump curve and the pressure drop curve of the respective
heating circuit distributor or further components (pipe assembly, dis-
tributor etc.).
The following pump graphs show the pressure drop curves of the dif-
ferent Divicon heating circuit distributors.
Maximum flow rate for Divicon:
■ with R ¾ = 1.0 m 3
/h
■ with R 1 = 1.5 m 3
/h
■ with R 1¼ = 2.5 m
3 /h
Example:
3
Flow rate ´ = 0.665 m /h
Selected:
■ Divicon with mixer R ¾
■ Wilo Yonos Para 25/6 circulation pump, variable differential pressure
operating mode and set to maximum delivery head
■ Pump rate 0.7 m 3 /h
VIESMANN
64
(cont.)
R 1¼
183
583
784
G 2
A
B
C
D
3
/h
1 3 5 10
Heating circuit output
in kW
C Divicon with mixer-3 (R 1)
Application range: 0 to 1.5 m
D Divicon with mixer-3 (R 1¼)
Application range: 0 to 2.5 m
² = µ · c · ΔT c = 1.163
kg · K
11600 W · kg · K
²
´ = =
c · ΔT 1.163 Wh · (75-60) K
Select the smallest possible mixer within the application limit with the
value ´.
Result of this example: Divicon with mixer-3 (R ¾)
Head of the relevant pump
curve:
Divicon pressure drop:
Residual head:
Note
For further components (pipe assembly, distributor, etc.) determine the
pressure drop and deduct it from the residual head.
Differential pressure-dependent heating circuit pumps
According to the [German] Energy Saving Ordinance (EnEV), circula-
tion pumps in central heating systems must be sized in accordance
with current technical rules.
Ecodesign Directive 2009/125/EC requires high efficiency circulation
pumps to be used throughout Europe from 1 January 2013, if the
pumps are not installed in the heat source.
5.0
2.5
2.0
1.5
1.0
0.5
0.2
0.1
20 30 40
3
/h
3 /h
Wh
´ (1 kg ≈ 1 dm³)
µ
kg m³
= 665 0.665
h h
48 kPa
3.5 kPa
48 kPa – 3.5 kPa = 44.5 kPa.
VITOLIGNO 200-S