A head pressure sensor is cheap assurance of accuracy. Just a single (or double) thermometer takes lots of trial and error to make the valve track reality. Most equipment mfrs state that pressure sensing at least doubles precision, even after dsp or modeling parameters.
Is this for your milk cooler valve heat pump? I am curious about it. I was waiting for some info on the beast, as it looks attractive in the sense that only one valve works both heating and cooling modes. Somewhat the same end result as EXV/EEV without additional electronics to be invented/made. Randy and Brad got their heat pumps going well enough to save ample energy, my window shaker finally shook itself to death before I could complete an autonomous controller for it.
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