23
OPERATING LIMITS
COOLING
-25
-35
-40
-30
-20 -15 -10 -5
0
5
10 15 20 25 30 35 40 45 50
Ta [°C]
0
5
-10
-5
10
15
20
LW
Tu
[°C]
BK
FC only
SUN
FU
Ta:
external air temperature
LWTu:
water outlet temperature from the user-side heat exchanger
FU:
in the indicated area, the control could actuate a forced capacity reduction of the compressors so as to prevent tripping of
the safety devices
FC only:
in the area indicated by the arrow, the switching on of the compressors is disabled and therefore the unit can work only in
free cooling mode
SUN:
to work in the indicated area, there must be no wind and the unit must be equipped with accessory "SUN Heaters for oper-
ation with air below -25°C". In this area, operation of the unit is guaranteed only by AC fans
BK:
For LWTu below +3°C, it is mandatory to fit the "Brine Kit" accessory
For LWTu below +5°C, it is compulsory to use suitable percentages of antifreeze additives (glycols) to prevent ice formation in the
exchanger.
The inlet and outlet temperatures of the user-side exchanger must be given on ordering to allow correct setting of the alarm parame-
ters and verification of the sizing of the expansion valve.
The cooling set point can then be changed by the customer in an interval that, compared to the set point given on ordering, ranges
from -1K up to the maximum temperature allowed by the above-stated operating limits.
The unit will be optimized to work at the set point temperatures given on ordering. For different set points, the cooling capacity pro-
vided and the level of efficiency of the machine could decrease and move away from these conditions.
