Ah ok that makes sense. So I misunderstood about what size check valve you said. You said liquid line, my mind instantly heard suction line. So I was think 7/8 but that is wrong. The liquid line is going to be 1/2", so I will grab a couple of them off ebay. I now have 2 of these balanced port txvs.
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It is a 2 - 4 ton range txv. They are both externally equalized but that is ok, I really really liked them.