EN
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13. STORAGE TANK
The following tables highlight principle char-
acteristics for hydraulic circuit components,
whilst the graph on the following page
shows relative static pressures.
13.1.
MINIMUM/MAXIMUM CONTENT OF
SYSTEM WATER
The minimum water content of system recommended
for units without hydronic kit is calculated using follow-
ing formula:
Volume = PFN(kW)
x 4
(l)= litres of system
PFN: Nominal cooling capacity
That resulting minimum water content necessary for
correct function of system.
The adjacent table indicates maximum water capac-
ity in litres of hydraulic plant, compatible with expan-
sion vessel supplied as standard IN THE VERSIONS
WITH STORAGE TANK OR PUMP ONLY. The values
shown in the table refer to three maximum and
minimum water temperatures. If the effective water
content of the hydraulic plant (including the storage
tank) is greater than that given in the table at opera
-
tional conditions, another dimensioned expansion
vessel must be installed, using thenormal criteria,
with reference to the additional volume of water.
In the following tables it is possible to work out the
maximum values of the system also for glycoled
water functioning.
Values are worked out by multiplying the reference
value by the corrective coefficient.
13.2. EXPANSION VESSEL CALIBRATION
Standard pre-load pressure value of expansion
vessel when empty is 1.5 bar, maximum value is
6 bar.
Calibration of the vessel must be regulated using the
maximum level difference (H) of the user (see diagram)
by using the following formula:
p (calibration) [bar] = H [m] / 10,2 + 0,3.
For example: if level difference (H) is equal to 20m, the
calibration value of the vessel will be 2.3 bar.
If calibration value obtained from formula is less than
1.5 bar (that is for H < 12.25), keep calibration as
standard.
ANL 100-150
Hydraulic height
H m
30
25
20
15
≥ 12.25
Calibration of expansion vessel
bar
3.2
2.8
2.3
1.8
1.5
Water content reference values
l
(1)
257
303
348
394
419
Water content reference values
l
(2)
116
136
157
177
189
Glycoled water
Water temp. °C
Corrective
coefficients
Recommended
conditions
max.
min.
10%
40
-2
0,507
(1)
10%
60
-2
0,686
(2)
20%
40
-6
0,434
(1)
20%
60
-6
0,604
(2)
35%
40
-6
0,393
(1)
35%
60
-6
0,555
(2)
Recommended operational conditions:
(1) Cooling: Max water temp. = 40 °C, min water temp. = 4 °C.
(2) Heating (hot air pump): Max water temp. = 60 °C, min water temp. = 4 °C.
KEY
(1)
Check that highest installa-
tion is not higher than 55
metres.
(2) Ensure that lowest instal
-
lation can withstand global
pressure in that position.
