AERMEC NRL, Техническое руководство по установке и обслуживанию

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3. CHILLER CIRCUIT
Compressors
High ef fi ciency scroll-type hermetic
compressors, assembled on elastic anti-
vibration supports, driven by a 2-pole electric
motor with internal thermal protection of the
electric heater casing included as standard.
The heater is automatically powered when
the unit stops, provided that the unit is kept
under tension.
Air side heat exchanger
High ef fi ciency device made of copper pipes
and aluminium blades locked into place via
mechanical pipe expansion.
Water side heat exchanger
Of the plate-type (AISI 316), externally
insulated with closed cell material to reduce
thermal dispersion. Fitted, as standard, with
antifreeze heater.
LIQUID SEPARATOR
(HEAT PUMP ONLY)
Located on the suction point of the
compressor, to protect against any fl owback
of liquid refrigerant, fl ooded start-ups,
operation in the presence of liquid.
Liquid accumulation
(only for heat pumps and total recovery)
To compensate the difference in volume
between the fi nned coil and the plate-type
exchanger, holding back excess liquid.
Filter drier
Of the mechanical type, made of ceramics
and hygroscopic material able to trap
impurities and any traces of humidity in the
chiller circuit.
Sight glass
For checking the refrigerating gas load and
any humidity in the refrigerating circuit.
Thermostatic valve
The mechanical type valve, with outside
equaliser on the evaporator outlet, modulates
the gas
fl ow to the evaporator on the basis of
the thermal load, in such a way as to ensure
the proper degree of overheating of the
intake gas.
Electronic valve (optional)
Liquid and discharge taps
(cooling-only versions)
They allow the refrigerant to be cut off during
extraordinary maintenance.
Solenoid valve
The valve closes when the compressor turns
off, preventing the
fl ow of refrigerant gas
towards the evaporator.
Bypass solenoid valve
(only for heat pumps)
To bypass the thermostat-controlled valve
during the defrosting cycle.
Cycle reversing valve (heat pump only)
Inverts the fl ow of refrigerant when
operation is switched between
summer/winter, and during defrosting
cycles.
Non-return valve
Allows the fl ow of refrigerant in one
direction only.
Desuperheater (only upon request)
Of the plate-type (AISI 316), externally
insulated with closed cell material to reduce
thermal dispersion.
Total recovery (only upon request)
Of the plate-type (AISI 316), externally
insulated with closed cell material to reduce
thermal dispersion.
3.1. FRAME AND FANS
Fan unit
Screw type, statically and dynamically
balanced. The electric fans are protected
electrically with thermomagnetic switches
and mechanically with metal anti-intrusion
grilles, in accordance with the standard CEI
EN 60335-2-40.
Enlarged fans (M)
These offer a useful head to overcome the
pressure drops in the system
Inverter fans (J)
Load-bearing structure
Made of hot-galvanised steel sheet of a
suitable thickness, varnished with polyester
powders able to resist atmospheric agents
over time.
3.2. HYDRAULIC
COMPONENTS
Circulation pump
Depending on the
characteristics of
the pump chosen, it
offers a useful head
to overcome the
pressure drops in the
system. There is also the
possibility to have a reserve pump.
The reserve pump is managed by the
electronic card.
Flow switch (installed as standard)
This checks that the water is circulating. If this
is not the case, it shuts down the unit.
Water fi lter(installed as standard)
Allows you to block and eliminate any
impurities in the hydraulic circuits. Inside, it
has a
fi ltering mesh with holes not greater
than one millimetre. It is essential for avoiding
serious damage to the plate-type exchanger.
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INRLPY. 02.10 4086916_01