Contaminated Refrigeration System

If this dark brown stuff is coming out of your filter/dryer when you push nitrogen through it, you can be sure that your sealed system is pooched. I tried everything I could to get this system dry, but it would restrict every time within about 2 mins of startup.  The only way to get this unit going again will be to replace evaporator, compressor, condenser and heat exchanger – pretty much the whole system. Not worth it on this one.