User Manual

4/16
Siemens Radiator valves CE1N2106en
Smart Infrastructure 2020-10-06
Engineering notes
The reference numbers for preadjustment are given in the table with the k
v
-values (see
page 5) and in the "Valve sizing charts" (see pages 7 – 7).
1.
Calculate the volumetric water flow
100V
&
1
100
100
f1.163
.
´D´
=
T
Q
V
[m
3
/h]
Q
100
= heat demand [kW]
ΔT = temperature differential [K]
1.163 = constant of water
f
1
= correction factor = 1 for water
2.
Define the pressure drop Δp
v100
across the fully open valve
In most types of plant, a differential pressure Δp
v100
of 0.05 to 0.2 bar is adequate.
3.
Calculation of the nominal flow value k
v
100
100
v
v
Δp
V
k
&
=
[m
3
/h]
Δp
v
100
= differential pressure across the valve
[bar]
Heat demand
Q
100
= 1
.
2 kW
Temperature differential
ΔT
= 20 K
Water volume
201.163
1.2
.
100
´
=V
= 0.052 m
3
/h
= 52 l/h
Required differential pressure across the
valve
Δp
v100
= 0.1 bar
Flow
0.1
0.052
=vk
= 0.17 m
3
/h
Solution
According to the chart (refer to "Valve sizing charts", or table with k
v
-values), the
preadjustment required for a VDN210 3/8“ valve is 2.
Tips
· Noiseless operation is ensured by a pump that provides no more pressure than is
needed to transport the required amount of water.
· To keep the valve free from dirt particles, it is recommended to install a strainer.
Example: