Proline PAC1500 Manual Del Usuario página 183

If compressors or compressor oils are to be removed, ensure that
they have been evacuated to an acceptable level to make certain
that flammable refrigerant does not remain within the lubricant.
The evacuation process shall be carried out prior to returning the
compressor to the suppliers. Only electric heating to the compressor
body shall be employed to accelerate this process. When oil is drained
from a system, it shall be carried out safely.
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