CLIMAVENETA W3000 compact, Техническое руководство, Страница: 35 / 104

C0240111-04-05-GB
6.1) FREECOOLING
The “freecooling” function is applied to the efficient production of cold water by using external air.
The operating principle is illustrated in figure 6.2 .
FREECOOLING
COIL
“3-way” valve
EVAPORATOR
water
air
Figure 6.2 : block diagram of the freecooling activation circuit
If the external water is cold, the valve closes and the water passes through the coil which cool the water
by the water-air heat exchange achieved thanks to the internal fans. If, instead, the air is hot, there is no
point in it passing through the coil and all the water is cooled with the evaporator compressors.
Further details of the valve and fan adjustment system are shown in figures 6.3.
1 0 0 %
% v a l v e
a p e r t u r e
T e x t .
T f c o o l .
D e l t a
- O n / O f f v a l v e
- M o d u l a t i n g v a l v e
Figure 6.3a : valve operation
T . in
O ffse t
C h ille r
S e tp o in t
% v a lve
a p e rtu re
D iff.
1 0 0 %
- O n /O ff va lv e
- M o d u la tin g v a lv e
Figure 6.3b : freecooling low temperature control (to prevent the coil from freezing)
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