30 AGL_HP_VS_YHV_RG_RT_EN_Rev00
5.5 Charging procedure
WARNING
Air/A2L or A3 refrigerant mixture in a potentially flammable or explosive
atmosphere! Fire and explosion hazard! Only use
designed and approved for use and operation with A2L or A3 ref rigerants.
Make sure all connections are tight to avoid leakage. Make sure to f ill with
pure A2L or A3 refrigerant.
Low suction pressure operation! Compressor damage!
with a restricted suction. Do not operate with the low-pressure cut-
Do not operate the compressor at pressures not allowed by the operating
envelope.
Allowing the suction pressure to drop below the envelope limit for
more
than a f ew seconds may overheat scrolls and cause early drive bearing
and moving parts damage.
Prior to charging or re-charging, the refrigerant system must be leak- and pressure-tested with
appropriate purging gas.
Ensure that the system is grounded prior to charging with refrigerant.
The system shall be liquid-charged through the liquid-receiver shut-off valve or through a valve in
the liquid line. The use of a filter dryer in the charging line is highly recommended. Systems shall be
liquid-charged on both the high and low sides simultaneously to ensure a positive ref rigerant
pressure is present in the compressor before it runs. The majority of the charge shall be placed in
the high side of the system to prevent bearing washout during first-time start on the assembly line.
Extreme care shall be taken not to overfill the system with refrigerant. The system manufacturer must
respect the charge limitations according to valid standards, such as EN 378.
5.6 Run-in time
Scroll compressors exhibit a slight decrease in input power during the initial running period.
Published performance ratings are based on calorimeter testing which is carried out after run -in.
Therefore, users should be aware that before the performance specified by EN 12900 is achieved
the compressor needs to be run in. Recommended run-in times f or YHV*RG/RT compressors to
attain the published performance are 16 hours at the standard conditions.
5.7 Initial start-up
High discharge pressure operation! Compressor damage!
compressor to test opening setpoint of high-
pressure limiter. Bearings and
moving parts are susceptible to damage before they have had several hours
of normal running in.
Liquid and high-pressure loads could be detrimental to new bearings. It is therefore important to
ensure that new compressors are not subjected to liquid abuse and high-pressure run tests. It is not
good practice to use the compressor to test the high-pressure switch function on the production line.
The switch function can be tested with nitrogen prior to installation and the wiring can be checked by
disconnecting the high-pressure switch during the run test.
5.8 Rotation direction
Scroll compressors, like several other types of compressors, will only compress in one rotational
direction. Variable speed compressors have three-phases and the drive is either for 1~ or 3~ phase
external power supply. Swapping phases between compressor and drive can result in reverse
direction, read caref ully compressor and drive manual. It is important to include notices and
instructions in appropriate locations on the equipment to ensure proper rotation direction
when the system is installed and operated.
Observing that suction pressure drops and discharge pressure rises when the compressor is
energized allows verification of proper rotation direction. There is no negative impact on durability
caused by operating three-phase Copeland scroll compressors in the reversed direction for a short
period of time (under one hour) but oil may be lost. Oil loss can be prevented during reverse rotation
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