YCAS Subcooler pressure

[Dilp172]

Got a unit i'm working on unit running ok but was wondering what a normal suction pressure/temp should be on the suction line going into the commpressor from the subcooler whe it is on line.Thanks for your k-noledge

[HJ Controls]

set the econ tev to 12 degrees superheat.

[henpeck]

I could be wrong, but I think you are supposed to see another 20 to 25 degrees farther subcooling thru the Plate heat exchanger.

[Dilp172]

I could be wrong, but I think you are supposed to see another 20 to 25 degrees farther subcooling thru the Plate heat exchanger.

I know that but where the gas connection into the comp. connects is it at an intermediate point in the compression stage and is it normally higher than the suction gas pressure from the cooler?

[henpeck]

So many variables come into play as for as just getting a pressure. I really couldn't tell you what that pressure normal runs come paired to true comp suction pressure. Sorry, I normally just wanted the subcooling and making sure that I had my superheat on the Econ. I'll have to see if I can find anything on it.

[klove]

What henpeck is saying is correct - the subcooler saturated temp goes up and down dramatically as the condenser actual temps vary. To look for a constant pressure, as in R-22 is 68.5 psig at 40 degrees saturated on an a/c evaporator (which is a normal baseline for a/c systems, but it's still not a constant), is asking for a constant world, which is non-existent. Pressure is not what you're shooting for - superheat is your target. I've checked quite a few, and if my readings are correct, the input is at an intermediate point, not at true suction.