AutoPilot Digital Newbie Question

[dan4jc]

Just installed my AutoPilot Digital SC-60 a few weeks ago and opened the pool this past Saturday. Before adding any salt, the Pool Pilot showed a salt reading of 1800ppm. I thought that was high, so I took a sample to Leslie's and they gave a reading of 1300. I added 280 lbs of salt Sunday, and the SWG was happy and reading 3000 ppm. Yesterday I took another sample to Leslie's and got the below numbers:

FC: 3.0
CC: 0
pH: 7.4
CH: 150
TA: 100
CYA: 50 (I have some CYA soaking in a sock right now)
Phosphates: 300
Salt: 1200 (actually lower than Saturday's reading, after I added 280 lbs of salt)

I took a different sample to another local pool place that uses the BioGuard computer analysis and got similar numbers; salt was 1600. Up to this point I've been using liquid chlorine until the numbers are close to where they should be before turning on the SWG. Water temp is around 60. I did order my TF-100 and the Taylor K-1766 kits yesterday and I'm looking forward to taking my own readings, but I do have some questions.

1) I know people have said before if the SWG is happy with the salt content, don't worry too much about it, but that seems like a big discrepancy. I'm anxious to see what the K-1766 reads. Is it ok to turn on my SWG now, or should I wait until a test with the K-1766?
2) Does water temp and/or phosphate level have any impact on the Pool Pilot salt reading? I wouldn't think so, but the guy at Leslie's implied that it would.

First year using the SWG, so I'm sure I'll have many more questions. But I'm excited to be getting my own testing kit and not have to make the dreaded trip to the pool store and have them tell me how badly I need to raise my calcium hardness.

Thanks!

 

[JasonLion]

You need to relax about the salt level. If the SWG is happy that is all that matters. The only time to doubt the SWG is when it reads lower than everyone else, and even then the SWG is still likely to be correct (because of the AutoPilot salt sensor design, which is better than most).

There is absolutely no way the second pool store reading could possibly be correct unless the first one was wildly wrong. Either way at least one of them is way off, and most likely both of them are just plain wrong. Pool stores are frequently shockingly bad at test results, it is not at all surprising that they are this far off. Believe your own testing, and stop even looking at what the pool store says.

Some SWG salt readings are very affected by water temperature. The AutoPilot units have better temperature compensation than most, and are usually correct despite temperature changes, though small errors can creep in at temperatures well out of the normal range.

Phosphates have nothing to do with anything, expect trying to get you to spend more money, and can be completely ignored.

 

[pooldv]

Another point on adding salt. Be careful if your water temperature is under 60. Two years ago I kept adding salt because my cell was giving low salt error and I ended up not having to add salt to my pool for two years. Fortunately, the Pentair IC40 continues to work in high salt condition, but most SWCGs do not and would require draining water to get salt down to appropriate level. I did need to add 120lbs of salt this spring, but I waited until my water got to 70 before I did and just used bleach until then. Because I was a little skeert!

And yes, it is OK to turn on your SWCG. Mine actually stayed on all winter, pretty dumb on my part, I'll turn it off next winter. Never even occurred to me!

 

[JoshU]

Hi Dan, I know I answered your e-mails as well however if any more questions come up please be sure to let me know.

 

[dan4jc]

Just a quick update. I received my Taylor K-1766 kit and tested this weekend. I thought it was very easy to use and read, although I'm sure the speedstir helped quite a bit. Results showing 2200 ppm salt. The water temp is rising slightly, and i noticed yesterday that the AutoPilot is showing a reading of 2800 ppm. I'm assuming as the water temp rises, these two numbers will get closer together, so I'll take everyone's advice and relax. I must say I love the ability to test my own water and not have to rely on running to the pool store. Thanks for all the help!