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Siemens
Combi valves PN 25 with flanged connections
CE1N4316en
Building Technologies
2018-04-18
Sizing
Basis of design
1. Determine heat demand Q [kW]
2. Determine temperature spread ΔT [K]
3. Calculate volumetric flow
Ζ ∴
Ζ ∴
Χ
√
√
<
h
l
K
T
163
.
1
1000
kW
Q
V
%
4. Select suitable Combi valve VPF53..
5. Determine dial setting using volumetric flow/dial presetting tables, see below.
Example
1. Heat demand
Q = 150 kW
2. Temperature spread ∆T = 6 K
3. Volumetric flow
h
m
h
l
K
kW
/
6
.
21
/
654
'
21
6
163
.
1
1000
150
V
3
<
<
√
√
<
%
Hint: You can also determine the volumetric flow using the valve slide rule.
4. Select Combi valve VPF53..
Ideally, Combi valves should be selected such that they operate at about 80%
of their maximum flow, enabling them to deliver spare capacity, if required.
Selection: VPF53.65F24
∆p
min
= 25 kPa
VPF53.65F35
∆p
min
= 55 kPa
5. Determine dial setting using volumetric flow/dial presetting tables:
VPF53.65F24
Volumetric flow
21.6 m
3
/h
Dial setting
3.6
VPF53.65F35
Volumetric flow
21.6 m
3
/h
Dial setting
2.7
Tables to determine the dial setting for a desired volumetric flow.
Dp min [kPa] based on volumetric flow; interpolate missing values.
Presetting range linear to VDI/VDE 2173
Presetting range linear
Presetting range not permitted
Nominal
flow
VPF53.50F16
16 m
3
/h nominal
v
˙
[m
3
/h]
2.5 3.2 3.8 4.5 5.3 6 6.8 7.5 8.3 9 9.8 10.5 11.3
12 12.8 13.5 14.3
15
Dial
Min.
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8
4
Δ
pmin [kPa]
6.5 6.5 6.5 6.8 7.1 7.4 7.7 8.0 8.8 9.6 10.4 11.2 12.0 13.5 15.2 16.8 18.5
20
VPF53.65F24
24 m
3
/h nominal
v
˙
[m
3
/h]
4.4 5.6 6.6 7.7 8.6 9.6 10.5 11.5 12.5 13.5 14.7 15.8 17.1 18.5 19.9 21.5 23.2
25
Dial
Min.
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8
4
Δ
pmin [kPa]
15.0 15.0
15 15.7 16.2 16.8 17.4 18.0 18.4 18.7 19.1 19.5 20.0 20.9 21.8 22.8 23.9
25
VPF53.80F35
35 m
3
/h nominal
v
˙
[m
3
/h]
5.3 6.9 8.3 9.6 10.9 12.2 13.5 14.8 16.2 17.6 19.1 20.7 22.4 24.3 26.4 28.7 31.2
34
Dial
Min.
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8
4
Δ
pmin [kPa]
16.0 16.0
16 16.4 16.8 17.2 17.6 18.0 18.4 18.7 19.1 19.6 20.0 20.8 21.7 22.7 23.8
25
VPF53.100F70
70 m
3
/h nominal
v
˙
[m
3
/h]
12.1
15 18 21 23 25 28 30 32 35 38 40 43 47 51 56 62
68
Dial
Min.
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8
4
Δ
pmin [kPa]
19.0 19.0 20.0 20.5 20.8 21.2 21.7 22.0 22.5 23.2 23.8 24.3 25.0 26.6 28.2 30.2 32.6
35
Engineering example
Volumetric flow/dial
presetting
Standard flow rate
