AGL_Ref_ST_YBK1E_EN_Rev01
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5.5
Charging procedure
WARNING
Air/A2L refrigerant mixture in a potentially flammable atmosphere! Fire
hazard!
Only use f illing equipment designed and approved f or use and
operation with A2L ref rigerants. Make sure all connections are tight to avoid
leakage. Make sure to fill with pure A2L refrigerant.
CAUTION
Low suction pressure operation! Compressor damage!
Do not operate
with a restricted suction. Do not operate with the low-pressure limiter bridged.
Do not operate compressor at pressures that are 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 ref rigerant 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 f ilter drier 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.
NOTE: For applications with A2L refrigerants, the system manufacturer/installer 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.
Theref ore, users should be aware that bef ore the performance specified by EN 12900 is achieved
the compressor needs to be run in. Recommended run-in times f or YB*K1E compressors to attain
the published performance are 16 hours at the standard conditions.
5.7
Initial start-up
CAUTION
High discharge pressure operation! Compressor damage!
Do not use
compressor to test opening setpoint of high-pressure cut-out. Internal 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 theref ore 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.
Switch f unction can be tested with nitrogen prior to installation and 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. Direction of rotation is not an issue with single-phase compressors since they will always
start and run in the proper direction. Three-phase compressors will rotate in either direction
depending upon phasing of the power. Since there is a 50-50 chance of connecting power in such a
way as to cause rotation in the reverse direction,
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
