Do you know if this car has a "continuously driven" AC compressor or the later "clutch enabled" version?
Really this car would need to have its HVAC controller scanned using a fully VW Group compliant scan tool, to reveal what or why this compressor is not "engaging" as it could be an issue elsewhere in the HVAC system that is forcing the AC compressor to protect itself - or it could be a proper AC compressor fault.
Edit:- sorry I forgot the "checked using OBD11 no faults showing" - unless OBD11 is failing to reveal some faults that it should be finding, maybe dig deeper and see which code is being generated concerning the non running of the compressor. If it is a "continuously driven" compressor, check to see if the pulley rubber protective coupling has sheared - if so, then it is "new compressor time".
