Regulus KPG1-ALC, Инструкция по установке и эксплуатации

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20
(Tab. 2 is valid for height up to 20 m only, otherwise the
size shall be calculated.)
8.1 - Expansion vessel sizing
A solar expansion vessel shall be sized for a tempe-
rature difference between the min. winter temperature
and the max. summer temperature. The working range
of expansion vessels is from -10 °C to +130 °C. Further
it shall be able to contain
fl uid volume of all collectors
in case of stagnation (max. collector temperature at
no
fl ow and high sunshine intensity). In solar systems
with forced circulation such pressure expansion vessels
shall be only used that are
fi tted with a propylene-glycol
resistant membrane and whose min. working pressure is
6 bar. Installation shall be done in a position with the dia-
phragm
fl ooded. In case the hear carrier starts boiling,
the diaphragm mustn’t get in touch with steam!
The recommended size of an expansion vessel see
Table 2
.
Tab. 2: Expansion vessel recommended size. Max. 30 m
of the inlet and outlet piping together.
8.2 - Calculation of a system working pressure
The pressure in the solar system is calculated using the
relation
p = 1.3 + (0.1 h)
p…pressure in a solar system [bar]
h…height from a pressure gauge to the middle of a col-
lector fi eld [m]
Adjust the pressure by discharging solar liquid after the
pressure test is done.
8.3 - Calculation of expansion vessel preset
pressure
Before fi lling the system, adjust the initial overpressure
in the expansion vessel to a value by 0.5 bar below the
calculated system pressure.
p
exp
= p - 0.5 [bar]
In order to set the pressure, use a current car-tyre pres-
sure gauge of a suitable pressure range.
The expansion vessel has a current tyre valve under its
lid.
8.4 - Examples of calculating working pres-
sure and expansion vessel pressure
8.4.1 - An example of calculating system working
pressure
The height from a pressure gauge to the middle of a
collector:
h = 10 m
Pressure in the solar system (the solar system is to be
pressurized to this value):
p =1.3 + (0.1 h) = 1.3 + (0.1 . 10) = 2.3 bar
8.4.2 - An example of calculating expansion vessel
pressure
Before fi lling the system, the preset pressure in the
expansion vessel shall be adjusted to the value of:
p
exp
= p - 0.5 = 2.3 - 0.5 = 1.8 bar
Number of
collectors
Expansion vessel
size
Max. piping
length
3 18 Max. 30 m of
the inlet
and outlet
piping
together
4 25
5 40
6 60
8 60
9 80
10 80
12 100
8. EXPANSION VESSEL SIZING AND WORKING PRESSURE CALCULATION
Fig. 27: Expansion vessel