I'm working on a pool with a Hayward SwimPure Plus SWP3, Calibration for Average Salt does not hold. Every few days I have to recalibrate. Exemple salt level drops from day to the other from 3100 to 700 ppm. My Cell is in very good state has been washed about 3 weeks. Is this problem cell related or control PWB related. Is there a troubleshooting documenttation on this unit
Thanks