I have a 3 ton Miami HP hpx series with 2100ft of ground loop. Yes I wish I had never bought it. They have no pressure charts for this particular model, the one they told me to use was for a water to water model. In any case it cuts out in second stage right at 80psig when ewt is 41 or lower. The pressures they listed for 40 ewt was 68-83, yet their pressure switch is 80psig!! My flow center is single pump, and looks like its only outputting 2 gpm per ton. I know it's low but I didn't think it was too low to affect heating. In any case I ordered a two pump one. Will increasing flow help me at all? I really don't want to go back to pump and dump. Operating pressures in heating mode is around 89 suction 322 liquid. Superheat is kind of high, it was 25 before it cutoff. subcooling normal. It didn't get a chance to run long enough for me to get the values to stabilize. I hope it's not the TXV.