Low Loss Header; Sizing The Solar Thermal System; Influence Of Orientation, Inclination And Shading - Viessmann VITODENS 242-F Technical Manual

Design information
Vitosol 200-T
Static head in m
Absorber area in m 2
2
3
4
Vitosol 300-T
2 Static head in m
Absorber area in m
2
3
4

Low loss header

See the Vitodens 200-W and 300-W technical guide.

6.6 Sizing the solar thermal system

Influence of orientation, inclination and shading

95
100
65
70
W
O
S
Shade reduces the energy yield
Position and size the solar collector array so that the effect of shade
creating structures, trees, etc. is minimised.
VITODENS
(cont.)
System capacity in l
5 25.1
10 28.1
15 31.6
5 29.2
10 30.1
15 33.6
5 31.8
10 34.9
15 35.8
System capacity in l
5 21.7
10 25.1
15 28.6
5 22.3
10 25.7
15 29.2
5 23.3
10 23.6
15 29.8
90
80
95
65
Recom. capacity of the ex-
pansion vessel in l
Recom. capacity of the expan-
sion vessel in l
The yield varies depending on where the solar collectors are installed.
The highest yields result from south-facing pitched roofs. In compari-
son, a roof with east-west orientation achieves only approx. 80 %
yield.
Depending on the purpose of the solar thermal system, we recommend
the following optimum angles of inclination for the collectors:
■ Solar thermal system for DHW heating
30 to 45°
This small collector angle of inclination takes the higher position of
the sun in summer into account.
■ Solar thermal system for central heating back up
45 to 60°
50
Taking the lower position of the sun in spring, autumn and winter into
account.
The deliberately large collector angle of inclination reduces periods of
stagnation in summer.
Recom. heat sink
(see page 71)
25 1.5 m uninsulated pipe
40 —
—
40 Type 21
50 —
—
40 Type 21
50
80 —
Recom. heat sink
(see page 71)
18 —
25
18
25
25 1.5 m uninsulated pipe
—
40 —
VIESMANN
6
73