Aquarite output dial not matched with output display

[Spano]

Is this a big deal? I noticed, when the dial is at below 50%, the display show about 5 % less. But when the dial is at 50%, the display show higher than the dial's and as I turn the dial to higher, the difference can be as high as 20. It matched at 100% though. I have been noticing this for a while but just ignored it until now, me 2 yrs old T-cell-15 starts making less and less chlorine with no fault indicators. All my chemical reading are fine, including combined chlorine. All previous cells lasted 3.5 yrs.

However, at setting below 50% on dial, readout shows 90%+.

 

[JamesW]

You probably need a new display board.

How To: Replace an AquaRite Display PCB - YouTube

Electrical contact cleaner might work. If you remove the display and spray the cleaner, it might clean the contacts enough to fix the problem.

Make sure that the instructions on the cleaner say that it is compatible with your type of circuit board. Allow the cleaner to dry thoroughly before reinstalling the board.