I've been running a 6800 reading for 2 weeks and a High Salt reading. For now the algaecide has kept it from being a lake.
I have an Aqua Rite 20 with software vers. 1.4 and a T-15 cell. The pool is about 8000 gal. The plates are clean and the salt levels should be around 2500. The system is about 4 years old. When I attempt to recalibrate (pressing Diag 5 times after switching from Off to Auto and after the click) the readings start at around 7000 then plummet to zero. I called Hayward last week and they said my control box was meant to have a T-5 cell which is why the readings are off with the T-15. I called the pool installer who said the arrangement should be fine especially since it was fine in the beginining (no help there). Do I buy a T-5 cell and swap out the T-15 cell or do I (or can I) swap out the circuit board for a software version 1.5 so I can set the TCell setting to T-15?