Pump down and suction pressure switches: legacy?

[Gary]

Being a radical departure from standard design practices, I would expect that the HX with TXV sensing bulb at it's outlet would be the least understood part of my design, so perhaps I should elaborate:

During the run cycle, this maximizes subcooling/minimizes flashing thus increasing the efficiency of the coil.

Placing the TXV sensing bulb at the HX oulet ensures that the superheat reaching the compressor inlet is the same as if the HX were not there (while maximizing subcooling).

During the off cycle, The HX forms a U shape with the coil, trapping any liquid in the coil and HX.

During defrost the HX, being within the refrigerated space, becomes the coldest part of the system; the part to which the liquid must migrate.