Refrigeration Questions

[sy_gilana]

Hopefully there are some clever peeps that can help me.

I have a R502 freezer with a 2.5 ton compressor and holding plate.
It is usually adjusted for 3 degrees of Superheat, TXV is 3 turns CW.
I want to run it less often but just as a cold box. It is inefficient at higher temps with the TXV that "tight". I want to open the TXV a bit, to raise the temp but increase capacity by flashing more gas.

Questions:

1 Will this work?

2 At rest the system reads 100 psi both sides, with the box at 16 °c 502 should be slightly lower, so if the box is at 16° and the rest of the system, (condenser, receiver, compressor etc) is at 30° is 100 psi about right, or do I have non condensing gasses in there?

3 Running, I have 180 psi high and 18 psi low, still have bubbles in SG but its behind the drier, only condensation on return line, no frost. Is that because of hi load or because of low charge?

Ideas please...