@Weener Dog posted:Guys, I'm not going to blow smoke up your rocket booster, I know nothing about these particular hvac units. My first job was in hvac (15 years) straight out of school. More than likely the black piping is flexible duct providing both supply and return air. In my opinion the duct work would be critical on a model to give purpose to the hvac unit. Thanks for posting John, very interesting topic.
Clearly the black pipes were for the air handler, and indeed they would certainly be crucial in the real world! 
