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▪ all valves in the correct running position;
▪ pressure and compound gauges fitted;
▪ correctly charged with refrigerant;
▪ compressor electrical isolator location & position.
5.5
Charging procedure
WARNING
Air/A2L refrigerant mixture in a potentially flammable or explosive
atmosphere! Fire and explosion hazard! Only use filling equipment
designed and approved for use and operation with A2L refrigerants. 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 few 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 refrigerant
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: 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.
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 for 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 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. 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
AGL_Ref_ST_YBK1E_EN_Rev03
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