GE water cooler R134A charge.

[romac]

Hi everyone.
I found it in a trash so now it's in my home and I decided to have practice on something so small I never had before. Compressor was running but not cooling. Sniffing with Inficon didn't reveal anything. Bubble test was negative as well so I tapped in a valve on low side and found not very much of pressure in it. Evacuated and filled with nitrogen (around 100psi) for overnight. It didn't loose pressure at all so I triple evacuated it and filled with some remaining fumes from 30Lb tank. It's cooling like a charm so I sniffed that again and no leaks. It takes 35 grams/1.235 oz of R134A. I didn't weight in the charge since I don't have that type of scale for a few of tears of ***** yet, not yet. When running, the low side is 5 psi. I would like to brass in shrader valve on the low side only.
1: Would be triple evacuating enough to remove those NCG brazing fumes so I don't have to install second valve on high side?
2: What would be the best way to charge the appropriate amount of ***** w/o buying small scale?
3: What kind of slow leak it developed so it can't be traced?, unless I missed the spot.
Thank you all.

[chillerman2006]

Hi romac

vapour charge - a tad at a time - let system settle - then a tad more - to superheat - trial & error - may have to decant & start again - small system critical charge

makes you wonder where original charge went/was it ever fully charged/working :confused:

[romac]

Thank you chillerman, I assume that it was running in the past since it has a greenish oxidation on the evap. from condensed moisture. High side is rated to 1.3 MPA/188Psi, I am thinking to pressure test the whole system to that pressure. What's the risk on the low side? Can it take the punch?

[chillerman2006]

Thank you chillerman, I assume that it was running in the past since it has a greenish oxidation on the evap. from condensed moisture. High side is rated to 1.3 MPA/188Psi, I am thinking to pressure test the whole system to that pressure. What's the risk on the low side? Can it take the punch?

Not sure as not familiar with that cooler, as I have it to hand I would leak check with helium which has a much smaller molecular structure than nitrogen...As a very clever tech once said to me, it's like comparing golf balls to beach balls