Setting up a used AC3 Pro. Went to calibrate a new BRS PH probe. In the 7.0 solution, settled on a reading of 7.05. In the high solution, still getting a settling around 7.06, then get a readming of 0.00 in the tank. Anyone have a similar issue that knows how to fix this?
Did you use the PH 7.0 solution and the PH 10.0 solution? You need both to get an accurate calibration. I did have the same issue with a brand new probe 2 years ago on my AC jr. It did in fact turn out that I had a defective probe. It's possible you just got a bad one. I got mine from Marine depot and they just shipped out a new one at no cost.
Are you rinsing the probe with RO water in between? It sounds like the 7.0 solution is maybe staying in the probe and its not getting a big enough difference in readings. Ken had a long post on here about what the difference needed to be, I think its somewhere buried in the Neptune section.
Also, there's a difference in the ACIIIP and the ACJR. You have to put the temp probe in with it. I cant explain why, just I remember something about that.