Need help. I have a phoenix machine that I can't get the ph meter to cal. I have swapped out ph board, ph probe and protective board with a known working one. I have used stablent 22 on the J18 and checked all voltages on the mother board.

Thanks in advance

My first suspect would be a bad probe. If you pulled a know good one out of another machine and it doesn't work, I would try taking the probe from the bad one and try it in the good machine. This is a good one, I'm not sure what my next step would be except to contact Gambro at 800-525-2623, they are usually very helpful. Please let me know what you find.