Low Loss Header - Viessmann VITODENS 222-F Technical Manual

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

Low loss header

See the Vitodens 200-W and 300-W technical guide.
5.6 Sizing the solar thermal system
Influence of orientation, inclination and shade
95
65
W
5
S
Shade reduces the energy yield
Position and size the solar collector array so that the effect of neigh-
bouring buildings, trees, etc. that cast a shade is minimised.
Installation options
VIESMANN
64
(cont.)
Static head in m System capacity in l
5
10
15
5
10
15
5
10
15
90
100
95
70
65
O
Recomm. expansion vessel
capacity in l
21.7
25.1
28.6
22.3
25.7
29.2
23.3
23.6
29.8
The yield depends on where the solar collectors are installed. The
highest yields result from south facing, pitched roofs. In comparison,
a roof with east-west orientation achieves only approx. 80 % yield.
Depending on the purpose of the solar thermal system, we recom-
mend the following optimum angles of inclination for the collectors:
■ Solar thermal system for DHW heating
30 to 45°
80
This small collector angle of inclination takes the higher position of
the sun in summer into account.
■ Solar thermal system for central heating backup
45 to 60°
Taking the lower position of the sun in spring, autumn and winter
50
into account.
The deliberately large collector angle of inclination reduces periods
of stagnation in summer.
For installation on walls or for horizontal installation on flat roofs, we
recommend sizing the solar collector area 20 to 30 % larger.
The Viessmann "ESOP" calculation program can be used to com-
pare different yields.
Recomm. heat sink
(see page 62)
18 —
25
18
25
25 1.5 m uninsulated pipe
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40 —
VITODENS