Low salt readings on Aqua Rite

[gfischer]

This my first post.
I am getting conflicting results and don't know which ones to believe.
I don't know how to rectify the situation.
I have an Aqua Rite Electronic Chlorine Generator.
At the end of last season, I found that my generator was displaying salt levels much lower than I was seeing with pool samples taken to the pool store.
Salt levels we at or slightly below the minimum value of 2700.
I thought that this indicated that my T-9 cell was going bad.

This season I installed an new aftermarket Compupool GRC/25GH.
I reset the controller for a T-15 cell.
My Generator currently indicates the following
2500 Instantaneous Salinity
Temp 64F
Cell voltage 26.8-27
Current 4.72 - 4.83
Desired output - now 50%
AL-0, revision 1.5 t-15 cell

Pool sample were as follows
Salt 3200
Chlorine was 6.6
PH 7.4
Total Alk 61
Cyanuric acid 39
Hardness 290

I have a 23000 gallon IG pool with a 1 HP two speed Pac-Fab Challenger pump with 250 lb sand filter.

How should I resolve the issue with the Salt Generator or my cell?

Thanks.

 

[JasonLion]

Welcome to TFP!

If the new cell reads about the same as the old cell, I would trust the cells far more than I would trust a pool store reading. The number of times we have gotten reports of wildly wrong pool store test results is staggering.

 

[gfischer]

Thanks. What would be a good product to sample and measure the salt level in the pool?

 

[chiefwej]

Just go by the readings on the control panel. What is important is to keep the system happy and working. Having a specific salt level is not critical. I usually run mine somewhere near the top of the unit's specified range to allow for back washing and splash out without having to add salt.

 

[frustratedpoolmom]

Right. If the cell thinks there is 2500 and won't produce till it thinks it is 3000, then put in 500ppm salt and see if it resolves the problem.

 

[zblaze]

When adding salt to your pool be sure to turn off T-cell. This protects the main circuit board damage due to a high amp draw. Leave the cell off for 12-24 hrs and then turn it back on. Next go to your diagnostic screen and press and hold the up arrow to reset the salt system levels. You then will get a correct reading on the ppm. This is for aqua logic systems and most others. Failure to disconnect the salt cell when adding salt can cause the K-1 relay on the circuit board to get to hot causing the weld on the legs to lose connection which results in a no cell power light. This problem develops over time.

 

[jimhokie]

This post caught my eye while searching for an answer on a different issue. I also have the Aqua Rite, and have had similar disparities between what my cell reads and what the pool store test reads. I have a theory maybe someone can confirm or refute. The first sample I took to be tested was at 2700, but the pool store said it was 3200. The second was 2500 (cell) and 2700 (store). The first time I took the sample on the morning and the bottle sat in my car all day. The pool temp was 64°, but when the store sampled it, it was 77° after sitting in my car all day. For the second test, I took the sample when the pool was 68° and immediately drove it to the store for testing. It read 71 when they tested it. So, a 13° temperature difference correlated to a 700 ppm salt difference, and a 3° temp difference correlated to a 200 ppm difference. Does cold water affect the calibration, skewing the salt reading lower that it actually is? That would be good to know before replacing your cell unnecessarily just because the water is too cold at the time. Or knowing this effect, you could keep the salt level at the lower end of the range when it's colder knowing that as the water warms up, the reading will also increase without adding more salt.