General information
56
EN
NCX and NXH units are shipped with a full operating charge
of refrigerant. Refer to table I.
If is nevertheless necessary to add more refrigerant, run
the unit for some time in cooling mode and then slowly
add liquid refrigerant into the suction side until there are
no bubbles in the sight glass.
NCX and NXH units use a R-410A refrigerant charge. For
your information, we are reproducing here some extracts
from the official publication dealing with the design, in-
stallation, operations and maintenance people involved
in these activities, agreed by the air conditioning and re-
frigeration industry.
Refrigeration guidelines
Refrigeration installation must be inspected and main-
tained regularly and rigorously by specialist. Their activi-
ties must be overseen and checked by properly trained
people.
To minimise discharge to the atmosphere, refrigerant and
lubricating oil must be transferred using which reduce
leaks and losses to a minimum.
If any oil draining or recovery operation becomes neces-
sary, the fluid transfer must be made using mobile con-
tainers.
• Leaks must be repaired immediately
• Service valves fitted the flow and return lines permit charge
transfer to a suitably arranged external container.
• It is indispensable to use a dedicated transfer station.
• Compressor lubricating oil contains refrigerant. Any oil
drainer from a system during maintenance must therefore
be handled and stored accordingly.
• Refrigerant under pressure must never be discharged to the
atmosphere.
Recharging liquid refrigerant
R-410A refrigerant operates at 50%-70% higher pressures
than R 22.
Be sure that servicing equipment and replacement com-
ponents are designed to operate with R-410A.
The cylinders that contain R-410A are pink.
The cylinders that contain R-410A re provided with a dip
tube that allows fluid to escape from the cylinder both
when upright position and when turned upside down.
Unit R-410A should be charged with liquid refrigerant.
Apply a common flow regulator available on the market
to the hose pipe to vaporize the liquid refrigerant before
is enters the unit.
R-410A, like other HFCs is only compatible with the oils
selected by the manufacturer of compressors (POE).
NOTE:
Regularly carry out leak check and immediately repair any
leak found
1.3 DESCRIPTION OF THE EQUIPMENT
NXC and NXH units are intended mainly for commercial ap-
plications such as the air-conditioning of offices and public
buildings.
NXC units are dedicated to cooling only applications.
NXH units operate instead both in heating and cooling mode.
All units use refrigerant gas R410A. The product is character-
ised by:
• Painted sheet frame;
• Scroll type rotary compressor fitted on anti-vibration sup-
ports;
• Electronically controlled fans able to ensure low noise op-
eration;
• Electronics integrated in the machine and controlled
through a microprocessor;
• Integrated hydronic kit equipped with centrifugal pump.
The machines have an operating range between -15°C and
40°C for NXH units and between -10°C and 48°C for NXC units.
The
Pro-
controller manages all parameters and the
operation of all main components (compressor, fans, expan-
sion elements …).
It also provides the possibility to:
• plan the operation using the internal clock and a program-
mable weekly calendar;
• control up to two units in parallel;
• limit fan speed, reducing their noise thanks to the “night
mode” function.
The unit can be also controlled with the following systems:
• Free contacts;
• Remote control.
