Since posting, I have surfed around and found a good link back in our archive on this site.
has good tech chat. Here's a piece:
Well you are not flushing the entire system, just the condenser and evaporator. You cannot flush the compressor the accumulator, the drier, or any mufflers. Hoses can be flushed but there is some speculation that mineral oil forms a barrier in rubber hoses. Flushing the condenser is easy because you can remove it, pour in some flush in one end and blow air through it to force it out. the evaporator is the hardest because it is embedded in the dash. Typically you use a flush bottle which is a cannister you fill up with flush solvent and pressurize with air. It forces the solvent into the evaporator, you follow up with compressed air to blow out as much as possible. As you are forcing in compressd air you put your finger over the outlet and do a what thay call "pop and blow", it helps build up pressure to remove more solvent.
For the compressor you remove it from the car and place it upside down on a bench and let gravity remove as much oil as possible. Then you pour in clean oil and turn the hub by hand until the oil begins to come out, repeat this until the oil comes out clean.
The system is assembled with a new accumulator/drier, new O rings and a vacuum pulled to remove moisture and flush remaining in the system.
Hope this helps......
Does the 190E have any in-line filters other than the rec/dryer?