FRIULAIR ACT ES 20-500, User Maintenance Manual And Spare Parts

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Technical description
22 – EN ACT ES 20 – 500
7.4 Refrigerating compressor
The refrigerating compressor is the pump in the system, gas coming from the evaporator (low pressure side)
is compressed up to the condensation pressure (high pressure side). The compressors utilized are
manufactured by leading manufacturers and are designed for applications where high compression ratios
and wide temperature changes are present.
The hermetically sealed construction is perfectly gas tight, ensuring high-energy efficiency and long, useful
life. Dumping springs support the pumping unit in order to reduce the acoustic emission and the vibration
diffusion. The aspirated refrigerant gas, flowing through the coils before reaching the compression cylinders
cools the electric motor. The thermal protection protects the compressor from over heating and over
currents. The protection is automatically restored as soon as the nominal temperature conditions are
reached.
7.5 Condenser
The condenser is the component in which the gas coming from the compressor is cooled down and
condensed becoming a liquid. Mechanically, a serpentine copper tubing circuit (with the gas flowing inside)
is encapsulated in an aluminum fin package.
The cooling operation occurs via a high efficiency fan, creating airflow within the dryer, moving air through
the fin package. It’s mandatory that the ambient air temperature does not exceed the nominal values. It is
also important to keep the condenser unit free from dust and other impurities.
7.6 Filter dryer
Traces of humidity and slag can accumulate inside the refrigerant circuit. Long periods of use can also
produce sludge. This can limit the lubrication efficiency of the compressor and clog the expansion valve or
capillary tube. The function of the filter drier, located before the capillary tubing, is to eliminate any impurities
from circulating through the system.
7.7 Capillary tube
It consists of a piece of reduced cross section copper tubing located between the condenser and the
evaporator, acting as a metering device to reduce the pressure of the refrigerant. Reduction of pressure is a
design function to achieve optimum temperature reached within the evaporator: the smaller the capillary
tube outlet pressure, the lower the evaporation temperature.
The length and interior diameter of the capillary tubing is accurately sized to establish the performance of
the dryer; no maintenance or adjustment is necessary.
7.8 Alu-Dry module
The heat exchanger module houses the air-to-air, the air-to-refrigerant heat exchangers and the demister
type condensate separator. The counter flow of compressed air in the air-to-air heat exchanger ensures
maximum heat transfer. The generous cross section of flow channel within the heat exchanger module leads
to low velocities and reduced power requirements. The generous dimensions of the air-to-refrigerant heat
exchanger plus the counter flow gas flow allows full and complete evaporation of the refrigerant (preventing
liquid return to the compressor). The high efficiency condensate separator is located within the heat
exchanger module. No maintenance is required and the coalescing effect results in a high degree of
moisture separation.