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CHARGING
These charging instructions apply to single fixed speed compressor circuit models.
NOTICE:
R-410A and R-407C refrigerants use Polyol Ester oil (POE) oil that
is prone to absorbing moisture. Therefore, the system should never be left
open to the atmosphere.
Package Air-Cooled Systems
Packaged air-cooled units come factory charged because all of the refrigerant carrying components
are self-contained with the evaporator and condenser sections. An air-cooled package unit may require
field charging if a compressor is changed, if a leak develops or if non-condensable are in the system.
Field charging should be done by referring to the unit electrical nameplate for the factory charge.
Although this value represents the original factory charge, it is still necessary to measure and note
proper unit operation including superheat, subcooling, head and suction pressure. Some adjustment to
charge may be required.
Charging/Installation Work Procedures
The basic installation work procedures are the same for R-410A and R-407C refrigerants. But the
working pressure for R-410A is 1.6 times higher than for R-407C. Therefore, some of the piping,
installation and tools are special.
Special Service Equipment for R-410A refrigerant
•
High pressure manifold gauge set suitable for R-410A pressure
•
High pressure recovery machine suitable for R-410A pressure
•
High pressure recovery tank suitable for R-410A pressure
(Ref: DOT 4BA400 or ABW400)
Triple Evacuation and Dehydration Procedure
Data Aire highly recommends a triple evacuation to be carried out on all Data Aire units to ensure the
highest quality moisture removal. Moisture prevents the proper operation of both the compressor and
the refrigeration system. Non-condensable and moisture reduces service life and increases
condensation pressure, which causes abnormally high discharge temperatures that can degrade the
lubricating properties of the oil. The risk of acid formation is also increased by non-condensable and
moisture and this condition can also lead to copper plating. These phenomena may cause both
mechanical and electrical compressor failure. The typical method for avoiding such problems is to triple
evacuate the system.
It is of the utmost importance that proper system evacuation and leak detection procedures be
employed. Good evacuation includes frequent vacuum pump oil changes and large diameter, short
hose connections to both high and low sides of the system (all refrigerant lines: suction line, discharge
line, and liquid line) preferably using copper tubing, vacuum rated or braided hose.
All valves in the system, solenoid valves, Thermal Expansion Valves (TXV), ball valves, and service
valves (if the compressor is equipped), need to remain open during the vacuum procedures and the
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