Vitosol-T
Absorber area in m
2
Static head in m
System capacity in l
Recom. capacity of the expan-
sion vessel in l
Recom. heat sink
(see page 106)
1.51
5
21.7
18 —
10
25.1
15
28.6
18
3.03
5
22.3
18
10
25.7
25
15
29.2
4.54
5
23.3
25 1.5 m uninsulated pipe
10
23.6
—
15
29.8
40 —
6.06
5
26.6
25 Type 21
10
27.5
40 —
15
31.0
—
7.57
5
27.8
40 Type 21
10
31.3
15
32.2
50 —
9.09
5
28.4
40 Type 21
10
31.9
15
32.8
50 —
10.60
5
29.0
40 Type 21
10
32.5
50
15
33.8
80 1.2 m uninsulated pipe
12.12
5
30.2
40 Type 21
10
33.7
50
15
37.1
80
15.15
5
32.0
40
10
35.5
50
15
37.2
80
Safety valve
The heat transfer medium is drained from the solar thermal system via
the safety valve if the max. permissible system pressure
(6 bar/0.6 MPa) is exceeded. According to DIN 3320, the response
pressure of the safety valve is the max. system pr10 %.
The safety valve must comply with EN 12975 and 12977, be matched
to the heating output of the collectors and be able to handle their max-
imum output of 900 W/m
2
.
Absorber area in m
2
Valve size (size of the inlet cross-section)
DN
40
15
80
20
160
25
Discharge and drain lines must terminate in an open container, capa-
ble of collecting the total capacity of the collectors.
Use only safety valves sized for max. 6 bar/0.6 MPa and 120 °C, which
bear the marking "S" (solar) as part of the product identification.
Note
The Solar-Divicon is equipped with a safety valve for up to
6 bar/0.6 MPa and 120 °C.
High limit safety cut-out
The solar control units Vitosolic 100 and 200 are equipped with an
electronic temperature limiter.
A high limit safety cut-out in the cylinder is required when less than
40 litres cylinder capacity is available per m
2
absorber area. This reli-
ably prevents temperatures above 95 °C in the cylinder.
Example:
3 Vitosol-F flat-plate collectors, 7 m
2
absorber area
DHW cylinder with 300 l cylinder capacity
300 : 7 = 42.8 l/m
2
,
e.g. a high limit safety cut-out is
not
required.
18.12 Additional function for DHW heating
DVGW W 551 specifies that the total water content must be maintained
at least at 60 °C and the DHW preheating stages must be heated once
every day to 60 °C.
■ Systems with a cylinder capacity, incl. DHW preheating stages, in
excess of 400 l
■ Systems with a pipework capacity in excess of
3 l from the DHW cylinder to the draw-off point
We recommend heating up in late afternoon. This ensures that the
lower cylinder area or the preheating stage is cold again following the
expected draw-offs (evenings and the following morning) and can sub-
sequently be heated up again by solar energy.
Note
For detached and two-family houses, this heat-up is recommended,
but not compulsory.
Information regarding design and operation
(cont.)
VITOSOL
VIESMANN
155
5822 440 GB
18