New to the forum but I have read a number of post concerning this topic. My question is, has anyone experienced an internal leak in one of these. By the design, I would say it would leak hot gas into the liquid line in the cooling mode. I have a low td, high head, high super heat, normal sub cooling and low suction. The indoor TXV was changed out and the charge weighed in without an improvement. We also have an unusual high frequency noise from somewhere in the condenser on the off cycle. 2002 Rheem high efficiency hp. 1 1/8 suction & 1/2 liquid lines, God only knows why.