Thanks a lot guys, it sounds like I am in for a pricey repair. Worthwhile though given the cooling capacity of the unit.
The internals can be seen
hereThe system uses what seems to be a non-standard version of the Embraco Aspera UNE6187Z condenser system, nameplate
here.
The compressor itself is Embraco Aspera model NE6187Z, nameplate
here.
There are worrying signs that the technicians that discarded this system removed something from the refrigeration system. There are signs of a pipe cutter.
If you look at
this picture there are two unterminated copper pipes. I also found a small terminated piece loose inside the unit. My knowledge of refrigeration systems is very limited, however I believe the one higher is the 'process line' of the compressor and the one lower is the return from the condenser coil which should normally carry liquid refrigerant? I am almost certain this is now an empty system, normally it uses R134a.
Replacing the compressor and filter/dryer (grey cylinder in-line) is one thing - my worry is they might have removed something critical?
Alex