C6.2.38/0719/E
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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, the 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 YBVH* compressors to attain the
published performance are 16 hours at the saturation evaporating and condensing temperature
conditions -10/45°C with a superheat of 10K.
5.7 Initial start-up
CAUTION
High discharge pressure operation! Compressor damage!
Do not use
compressor to test opening set point 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.
Switch function 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 Start and stop routine
The drive controls the start and stop routine of the variable speed scroll. This routine allows for soft
starting and controlled stopping, an advantage over traditional on/off control of fixed capacity units.
For more information about this topic please refer to the Emerson User Manual for ED3.
5.9 Starting sound
During the very brief start-up, a clicking sound is audible, resulting from initial contacting of the
spirals; this sound is normal. Due to the design of the Copeland scroll compressors, the internal
compression components always start unloaded even if system pressures are not balanced. In
addition, since internal compressor pressures are always balanced at start-up, low-voltage starting
characteristics are excellent for Copeland scroll compressors.
5.10 Deep vacuum operation
CAUTION
Vacuum operation! Compressor damage!
Copeland scroll compressors
should never be used to evacuate refrigeration or air-conditioning systems.
Operating scroll compressors in deep vacuum could damage internal motor
parts and lead to unacceptable high temperatures in the compressor housing.
5.11 Shell temperature
5.12 Shell temperature
The top shell and discharge line can briefly but repeatedly reach temperatures up to 135°C. Care
must be taken to ensure that wiring or other materials that could be damaged by these temperatures
do not touch the shell.
5.13 Pump-down cycle
WARNING
Vacuum operation! Creation of a flammable mixture! Fire hazard!
During
operation in vacuum a flammable mixture can form inside the system. Extreme
attention shall be paid to system tightness. Prevent ambient air from entering
the system. Pumping down outside the operating envelope or below
atmospheric pressure is not allowed. If this happens, immediately stop the
compressor and/or de-energize the power supply of the compressor.
