Riello NXHP Series Installation, Operation And Maintenance Instructions page 61

4 -OPERATION
4.3.2 - Compressors
NXHP units use hermetic rotary compressor. It is driven by a
variable frequency drive (VFD). The rotary compressor
incorporates an oil coil heating inside the shell.
The compressor sub-assembly is complete with:
■ Anti-vibration mountings between the unit and the compressor
chassis.
The compressors installed in these units have a specific oil charge.
NOTE: Do not use refrigerants and lubricant besides those
specified. Do not compress air (there must be no air intake
due to leakage in the refrigeration cycles).
4.3.3 - Air evaporator/condenser
The NXHP coils are heat exchangers with internally grooved
copper tubes with aluminium fins.
4.3.4 - Fans
The fans are driven by permanent magnet synchronous motor. The
motors are managed via a variable frequency drive (VFD).
According to the applicable regulation, the table below shows the
Ecodesign requirements for fans driven by motors with an electric
input power between 125 W and 500 kW
NXHP
Overall efficiency
Measurement category
Efficiency category
Target efficiency level ERP2015
Efficiency level at the optimum
efficiency point
Variable speed drive
Year of manufacture
Fan manufacturer
Motor manufacturer
Fan PN
Motor PN
Nominal power of the motor
Flow rate
Pressure at optimum energy efficiency
Nominal speed
Specific ratio
Relevant information to facilitate the
disassembly, recycling or removal of
the product at the end of the life
Relevant information to minimise the
impact on the environment
NOTE : NXHP 004 and 006 models are not concerned with
this table because their fans have an input power lower than
125 W.
008 - 010 - 012 - 014
% 41,3
A
Static
N(2015) 40
52,6
YES
See label on the unit
Complast Industrie
SRL
Nidec
C025223H01
UM100570A
kW 0,16
m /s 0,97
3
Pa 58,6
rpm 950
1,001
See Maintenance
Manual
See Maintenance
Manual
4.3.5 - Pulse Motor Expansion Valve (PMV)
The PMV is equipped with a stepper motor (0-500 pulses).
4.3.6 - Water evaporator/condenser
The evaporator/condenser is a plate heat exchanger. The water
connection of the heat exchanger is a threaded connection. It has
a thermal insulation of 6 and 13 mm thick polyurethane foam as
standard.
The products that may be added for thermal insulation of the
containers during the water piping connection procedure must be
chemically neutral in relation to the materials and coatings to which
they are applied. This is also the case for the products originally
supplied by the manufacturer.
NOTES - Monitoring during operation:
■ Follow the regulations on monitoring pressurised equipment.
■ It is normally required that the user or operator sets up
and maintains a monitoring and maintenance file.
■ If they exist follow local professional recommendations.
■ Regularly check for possible presence of impurities (e.g.
silicon grains) in the heat exchange fluids. These impurities
maybe the cause of the wear or corrosion by puncture.
■ The reports of periodical checks by the user or operator must
be included in the supervision and maintenance file.
4.3.7 - Refrigerant
NXHP units operate with refrigerant R-290.
4.3.8 - Receiver
NXHP 008, 010, 012 and 014 units are equipped with mechanically
welded storage tanks that stores the excess refrigerant when the
unit operates in heating mode.
4.3.9 - Four-way valve
For NXHP units, this device permits the reversal of the refrigeration
cycle to allow operation in cooling mode, in heating mode, and
during defrost cycles.
4.3.10 - Inverter subassembly for compressor and
fans
The NXHP units are fitted with Inverter modules to control the
compressor and the fan motors.
4.3.11 - Accumulator
The NXHP units are fitted with an accumulator in the compressor
suction line to prevent liquid carry-over to the compressor,
particularly during defrost cycle and transient operations.
4.3.12 - High-pressure safety switch
NXHP units are equipped with automatically reset safety pressure
switches on the refrigerant high-pressure side. For the alarm
ackowledgement procedures, refer to § 6. Alarm description.
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