SystemAir SYSCROLL 20-35 Air, Руководство по установке и обслуживанию

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7 - Product Description
7.1 General Information
Units are one-block type with one refrigerant circuit. They are
intended to cool down the water required for any air-conditioning
application as well as any other fluid, such as for example glycol
water.
These units are completely assembled at works. They are equipped
with all the refrigerating connections and the internal electrical wiring
required for a rapid installation on the field.
An operation test is performed after assembly, with water flowing
through the refrigerant/water exchanger in order to make sure that
every refrigerating circuit is properly working. The refrigerating
circuits of every unit are pressure tested before inspection, drained
and charged with R410A.
A low noise level is the result of a careful study. It is achieved on
chillers by using technologically advanced components without
negatively affecting the operation performances and limits of the
units.
Models operating in cooling mode can cool down chilled water at a
temperature b 18 and - 8 °C.
Heat pump models can warm up water at a temperature between 25
°C and 55 °C.
All units can operate with a double set point.
Body and Frame
The base and frame of these units are made with galvanized steel
elements, assembled with stainless steel screws. All panels can
be removed to ensure easy access to internal components. All
galvanized steel parts are protected by epoxy powder paint.
Compressors
The models are equipped with a single SCROLL compressor with an
internal motor protection.
The compressors of all models are assembled on rubber shock
absorbers. Their motors can be directly started. They are cooled
down by the aspirated refrigerant gas and equipped with internal
thermistor protections against overloads.
Overload protections are automatically reset after having tripped. The
compressor terminal box has an IP21 protection degree.
Compressors are powered on and off by the microprocessor of the
unit control system which is intended to control the delivery of the
thermal refrigerating capacity.
Evaporators
Evaporators are made of stainless steel plates. They are thermally
insulated by means of a thick flexible insulating mattress with closed
cells. The maximum operating pressures correspond to 10 bar
for the water side and to 45 bar for the refrigerant side. Antifreeze
protection for the water in the exchangers is ensured by electrical
heaters and differential pressure switches. The water side of these
exchangers is connected by manifolds which will provide for the
connection to the plant by means of one single 1”1/2 (for the size 20-
35) and 2” (for the size 40-75)gas threaded attachment.
Condensing coils
Condensers are made of copper tubes arranged in staggered rows
and mechanically expanded inside an aluminium finned pack.
The maximum operating pressure on the refrigerant side of the
condensing coils is 45 bar.
Condenser Fans
The condenser fans are of a helical type. They are directly coupled
and have an impeller with wing contoured aluminium blades.
Each fan is equipped with a galvanised steel accident-prevention
protection which is painted after manufacture. The fans motors
are completely closed. They have an IP54 protection degree and a
protection thermostat embedded in the windings.
Fans Control
All models are equipped with a fan speed controller as a standard.
It will act according to condensing pressure and allow the operation
down to – 10 °C outdoor air temperature.
Refrigerating Circuits
Each unit has a single refrigerating circuit equipped with an external
service valves intended to measure the refrigerant pressure and
charge, a sight glass with a humidity indicator, a dryer filter and a
thermal expansion valve.
Refrigerating circuits are also complete with a high and low pressure
switch as well as a high pressure transducer.
Control Supply Panel
All components of the control system and those necessary to start
the motors are shop connected and tested. The control compartment
contains an electronic card and a control board with an external
keyboard and display, to show the operational functions, as well as
the intervention of the alarms and the working blocks.