Viessmann Vitodens 200-W B2HE, Техническое руководство

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²
=
µ
· c · ΔT c = 1.163
Wh
kg · K
µ
²
c · ΔT
=
kg
h
´
=
11600 W · kg · K
1.163 Wh · (75-60) K
= 665
m³
h
0.665
´
(1 kg ≈ 1 dm³)
Select the smallest possible mixer within the application limit with the
value
´
.
Result of this example: Divicon with mixer-3 (R ¾)
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:
Flow rate
´
= 0.665 m
3
/h
Selected:
■ Divicon with mixer R ¾
■ Wilo Yonos PARA 25/6 circulation pump, variable differential pres-
sure operating mode and set to maximum delivery head
■ Pump rate 0.7 m 3
/h
Head of the relevant pump
curve:
48 kPa
Divicon pressure drop: 3.5 kPa
Residual head: 48 kPa – 3.5 kPa = 44.5 kPa.
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), circu-
lation 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 generator.
Design information
The use of differential pressure-dependent heating circuit pumps
requires heating circuits with variable pump rates. These include e.g.
single and twin line heating systems with thermostatic valves and
underfloor heating systems with thermostatic or zone valves.
Wilo Yonos PARA 25/6
■ Particularly power saving, high efficiency circulation pump
■ Energy efficiency index EEI ≤ 0.20
Operating mode: Constant differential pressure
40
0
10
20
30
0
100
200
300
400
0 0.5 1.0 1.5 2.0 2.5
Flow rate in m³/h
Pressure drop/head mbar kPa
50
500
60 600
3.0 3.5
70
700
Δp-C
max.
C
B
A
A
Divicon R ¾ with mixer
B
Divicon R 1 with mixer
C
Divicon R ¾ and R 1 without mixer
Operating mode: Variable differential pressure
40
0 0
100
200
300
400
0 0.5 1.0 1.5 2.0 2.5
Flow rate in m³/h
Pressure drop/head mbar kPa
50
500
60 600
3.0 3.5
70 700
Δp-V
max.
A
C
B
10
20
30
A
Divicon R ¾ with mixer
B
Divicon R 1 with mixer
C
Divicon R ¾ and R 1 without mixer
Installation accessories
(cont.)
88
VIESMANN
VITODENS
7
5853906