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NLC UNIT OPERATION
The chillers and the heat pumps of the NLC range are air-cooled machines suitable
for installing indoors.
For this reason the air that crosses the coil needs to be expelled from the utility
room using suitable piping connected to the machine itself.
The presence of the piping involves pressure drops that will need to be overcome
by the fan; the size of these losses depends on various factors like the length of the
pipe, the dimensions, complexity of the pipes, etc.
The units of the NLC series are equipped with radial fans with inverter
EC motor as standard, to immediately modulate the number of motor
revs, thus adapting the static pressure supplied from the fan to the in-
stantaneous drop of pressure in the tube.
When the machine is started for the first time, the installer should
set (from the control panel) the number of revs of the fan capable of
providing head equal to the total pressure drops of the piping.
The number of fan revs is generally less than the maximum number of
revs the fan is capable of.
0
10
The number of revs is set indirectly through a
parameter expressed in volts, which can vary
from 0 to 10V:
Min.
fan speed
Max.
fan speed
Volt
All the units are factory-set for 0 Pa.
To change the static useful pressure of the fans, follow the procedure set
out in the manual USE - INSTALLER MENU
Remove the safety protections before carrying out the connection to
the air exhaust ducts.
standard version
In case of inverted channeling from the standard, unscrew the screws
and invert the plenum panel as shown in the picture.
