Best settings for Autopilot

[Tominthedesert]

This is our second year with Autopilot Dig 220 36-Cell. I think I am finally starting to understand the chemistry and the unit. Still need some help for the best settings on the SWG for optium usage, cell life and controlling rising pH values. Last year I struggled with rising pH issues had to add a pint of acid a day. Got a little lax towards the end of last year. Now I have scale bumps on the plaster. Its too hot now to drain the pool and do an acid wash. BLAH Blah... To my questions, I am still not sure what I should set my SWG at power cell 1 or 2? Currently with a water temp of 80.. power level 1 uses 80% power level 2 uses 20% I have it on for 6 hours a day and the chlorine seems to be staying at 3 ppm. Along with getting my borates to 50ppm to help with the pH swing what else can I do? More hours a day different power setting.. Anything else with my pool chemistry?

Free Chlorine=3
Total Chlorine=3
pH 7.6
Total Alkalinity= 60 (is this too low?)
Calcium Hardness 500 ppm (we have extremely hard water in Phoenix)
Cyanuric Acid= 80
Salt =3700 ppm
borates ? waiting for test strips (added 7 boxes of 20 mule so far. I am calculating I will need to add about 12 boxes)
IG 15,000 gallon

[Poolsean]

Hey Tom,

Either way is fine and will provide equal cell life. My opinion is to keep the output between 25 - 75% output to accomodate the changes in water temperature, and temp compensation.
As your summer heat is not quite here yet, I 'd recommend using Cell Power 2 and 20% as your normal configuration. You have enough adjustments to increase the output to maintain the chlorine demand when it gets hotter.
If you use Cell Power 1 @ 80%, there's little adjustment, and you may eventually have to increase to Cell Power 2 anyway.

Chemistry is good, given your Calcium hardness being so high. In another post, Waterbear has mentioned that borates of 50 ppm has helped to decrease his acid requirements. Once you get your borates test results, let us know, and I'm sure Waterbear can offer advice from there.

Hope this helps.