Solar Coverage - Viessmann VITODENS 242-F Technical Manual

Design information
Installation options

Solar coverage

70
60
50
40
30
20
10
300 350 400
Energy (yield) in kWh/(m²/p.a.)
A Conventional sizing for DHW systems in detached houses
DHW demand of apartments
The following details are required for an estimation of the required
solar collector area.
Determining the required solar collector area
Note
Select the solar collector area only within sizing limit
oversized solar collector areas can lead to stagnation.
VITODENS
(cont.)
450 500 550 600
H , since
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.
The solar coverage indicates what percentage of the annually
required energy for DHW and central heating can be covered by the
solar thermal system.
Designing a solar thermal system always entails finding a good com-
promise between yield and solar coverage. The higher the selected
solar coverage, the more conventional energy is saved.
However, this is linked to an excess of heat in summer. This means
a lower average solar collector efficiency and consequently lower
yields (energy in kWh) per m 2 absorber area.
DHW demand:
■ Standard demand: 30 - 40 l/day and person
■ Higher demand: 40 - 60 l/day and person
Example for the following sizing aids: Detached house with 4 occu-
pants, Vitosol 300-T solar collectors.
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VIESMANN
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