Airedale EcoChill 6kW - 46kW - Manual (Page 32)

32
EcoChill Chiller
Technical Manual 7300221 V1.1.0_02/2013
11. STORAGE TANK
The following tables highlight
principle characteristics for hydraulic
circuit components, whilst the graph
on the following page shows relative
static pressures.
11.1. MINIMUM/MAXIMUM SYSTEM
WATER CONTENT
The minimum system water content
recommended for units without
hydronic kit is calculated using
following 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 capacity in litres of hydraulic
plant, compatible with expansion
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 operational 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 glycol functioning.
Values are worked out by multiplying
the reference value by the corrective
coefficient.
11.2. 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.
ECL 020-025-030
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) 103 121 139 158 168
Water content reference values l (2) 46 55 63 71 76
ECL 040-050-080-090-100-150-200
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 instal-
lation is not higher than 55
metres.
(2) Ensure that lowest instal-
lation can withstand global
pressure in that position.