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i will try to help you on this one. The unit does sound like it is over charged! this is usually what happens when someone tries to charge the unit in cooling mode during cool weather. My suggestion is to either wait for warmer weather (65 or higher) and check the system charge in cooling or keep removing refrigerant (according to EPA guidelines of course) a little at a time until the compressor bypass no longer engages.
I dont think you have a restricted drier or faulty rv at this time.
I went back to the home last Friday; temps were near 70 deg F. I turned the system on to "cool mode" and the pressures were 160/45... the evaporator at the AHU was freezing up. So I don't think it's overcharge. I am currently poised to replace the outdoor TXV as I suspect it is restricting refrigerant. In "heat" mode the head pressure spikes almost getting up to 400 psig before the system is cut out on 'high pressure'.
So, do you think my premise is plausible?
Well not sure. Did you happen to see frost near the TXV or RV showing a restriction?
You also have a check valve in the evaporator coil that might be stuck... if you can get to this you should try tapping on it. Some of the newer check valves are in the evap TXV.
what is the pressure at the "all time" suction port in heat mode. If the head pressure is spiking at 400 psi, but the all time suction is going to 0 psi, then the outdoor TXV needs to be replaced. Try this and let us know!
If the all time low is going down to 0 psig and the head pressure (at the liquid line port) is going to 400 psig, then it is a bad outdoor TXV.
If it were the indoor check valve (or anything else between the compressor hot gas line and liquid line port), then the pressure at the liquid line port would be at 0 psig also.