Head pressure exceeds maximum rating (550) 575+ on liquid line. Runs well in cool mode.But not in heat mode. Heat mode : 110 true suction. od temp=50 liquid line temp= 93 Compressor is drawing 13.7 amps.(RLA is 14.1) Air flow is good in and out. unit is about 18 months old and is matched. coils are clean in and out. Ran with return duct removed to eliminate any return air issues.(no change) Suspected outdoor txv. Got a second opinion. I replaced the condensing unit with my spare unit. (same model , figured I would replace txv at the shop and not have to stand on my head!) The new condensing unit performed exactly like the old one. This doesn't leave much but the txv in the air handler. What am I missing?

Heating & Cooling - Ruud