3) The old system pump WAS fixed enough to become functional, and though I had very recently replaced the 5th stage on that new unit, the service department at that store replaced the 5th stage when they worked on that unit. VERY unfortunately, this technician not only again mixed the tubing flow, BUT he reversed the flow so as to feed stage 5 from a line out that had always been the line in! I tried giving his plumbing flow a benefit of the doubt, but he was again proven wrong by the water heated for coffee. I restored the flows to the way they worked for 6 years, but the flow through that unit remains salted. The stage 4 step is broken, I don’t know why or how.