What you're seeing is where my accumulator used to be. It's been left like this for about a week. It's not air tight, but it's sealed up pretty well. I just put fresh PAG oil in the compressor last weekend. My question is, did the PAG oil absorb a ton of moisture in the past week by leaving it like this? Should I drain and refill the compressor again? Or would vacuuming it down be enough to get rid of any moisture?