Salt Reading Discrepency with Autopilot

[hzz]

My Autopilot says the salt level is 3300, but according to the test strips it is only 2000.

Which one am I to believe? The Autopilot is producing chlorine with no problem.

Not sure if I need to calibrate the Autopilot for salt. This is my third season with it and have never had to recalibrate before.

[PatL34]

Get yourself the Taylor Salt Test kit (Item# K-1766). I just tested my pool with test strips, and it was off as well. That's how unreliable they are.

Then you can calibrate your Autopilot.

Pat

[estermer]

I recently added salt to get my pool to 3000ppm. I used test strips to get that reading. My SWG wouldn't even generate salt becuase it said there was not enough.

Test strips are horrible! Get a drop kit.

[JoshU]

Some strips out there are good and some aren't.

Remember, that they do expire and will no long provide proper results when they're past their expiration.

[nater]

As stated above, ditch the strips and get a drop kit. Taylor's can be ordered online, as well as Ben's.

Once you can verify the salt level, go to www.autopilot.com and download the manual for your unit. That will tell you how to calibrate.

I've got a DIG-220, and I recalibrated it after installation. I figure it it's +/- 100 ppm vs. the drop test, it's good to go.

[waterbear]

Actually, the Aquacheck salt strips are not that bad. I have checked them against a properly calibrated Goldline salt meter (and also got the same salt reading as the Goldline meter on a MyronL meter when a local pool store did the test) and the salt strips only read 50 ppm less. The readout on my Goldline ps-8 SWG read 100 ppm higher than the 2 meters.

However, a drop based salt kit has a much greater accuracy than the strips which vary in accuracy with the salt level (accuracy resolution goes down as salt level goes up). so at higher salt levels your accuracy might be on the order of about 500 ppm vs. 200 ppm for the drop based test.

[Poolsean]

The Quantab salt strips (not the quick read type) are good and accurate provided that you store and remove the strips properly, and the strips are not swapped with another bottle (as the strips are calculated to the range on that specific bottle). Make sure your hands are dry before removing a strip. Store the bottle out of direct sunlight.
Why is your AutoPilot reading differently from the test strip? Most likely the strip is bad...just a drop of water in the bottle will contaminate the rest of the bottle. May as well toss it out.
If you do a TEST POOL PILOT, the displayed Cell Amps and Volts will indicate if your salt is actually low. As salt levels fall, the voltage increases. Depending on the model cell, there is an acceptable voltage range. The amperage should hold steady and is based on the Cell Power setting.

Hope this helps.

[hzz]

I have the SC-60 cell, and my readings are 25 volts and 4.8 amps.

How does that sound?

[Poolsean]

Sounds good if you're at cell power 1. Actually, it sounds like a little more than 3000 ppm.

[hzz]

I am at cell power 1, and that fits with what my Autopilot says....3300ppm salt.

So much for the test strips....