Autopilot-question about chlorine production just keeps going up


Well-known member
Aug 3, 2016
syracuse NY
Hi-I have an autopilot Aquacal Digital nano it is five years old, when I opened my pool the FC was zero, I ran the digital nano at 50% (purifier) for chlorine production. 24 hours later I see that it bumped up to 67%, I know the digital nano is supposed to increase chlorine production if it senses low chlorine (it says something like that in the owners manual) I did a water test 48 hours after turning it on and the FC was 5, so I lowered the purifier to 20%. I have been having a hard time regulating it to keep the FC between 2.5-3.5? The FC just keeps climbing then I have to unplug the salt cell and let the FC fall. Could this be a bad cell? Is it just getting old? I started having this issue last summer...