K-1766 salt test kit differing from the SWG reading?

[cflannagan]

After going through an ordeal (background: AquaRite reading 0 for salt level), it was finally determined my T9 cell was dead (failed testing at pool store). Replaced it with brand new T15 cell (the one with 3-year warranty).

Installed it, updated AquaRite setting to T15. Did the salt reading reset thing (OFF, wait for click, press display 5 times to get Instant Salt level (negative number), then used Super Chlorinate to reset it.

The SWG reading is showing 3100. The K-1766 salt test kit is telling me salt level is between 3400 to 3800 (it was 3400 couple of days earlier, and it's now 3800 for some reason when I haven't added more salt).

Will the salt level reading on SWG eventually rise? What makes me think it will not is when I go to the Instant Salt level, the number is lower (showing -2900). How critical is it to have the K-1766 reading match the SWG reading as closely as possible?

 

[ajw22]

SWG salt readings are accurate +/- 500 ppm. In other words, not very accurate.

K-1766 should be pretty accurate and repeatable.

If your SWG is happy with the salt level and generating CL? That is all that matters.

The K-1766 tests help when the SWG says high or low salt. Then it is best to test with the K-1766 and check if the pool salt level is good but the SWG salt sensor has failed before you start adding salt or draining the pool.

 

[cflannagan]

SWG salt readings are accurate +/- 500 ppm. In other words, not very accurate.

K-1766 should be pretty accurate and repeatable.

If your SWG is happy with the salt level and generating CL? That is all that matters.

The K-1766 tests help when the SWG says high or low salt. Then it is best to test with the K-1766 and check if the pool salt level is good but the SWG salt sensor has failed before you start adding salt or draining the pool.

Yeah, as far as I can tell, SWG seems happy. Generating LED is on, nothing is flashing. Looks completely normal to me. I haven't owned the K-1766 salt level test kit for long, so I wasn't sure how common the difference is - good to know it's +/- 500 ppm (which would seem like significant difference).

I normally try to main salt level of 3500-3600 based on SWG reading in the past, and since it's at 3100 now (I'll give it a week for the reading to stabilize), shouldn't hurt to add one salt bag (normally rising 250-300ppm for pool) right? On second thought, maybe not since winter is coming, so I don't really need as much salt - until I open the pool for the next swim season.

 

[ajw22]

I normally try to main salt level of 3500-3600 based on SWG reading in the past, and since it's at 3100 now (I'll give it a week for the reading to stabilize), shouldn't hurt to add one salt bag (normally rising 250-300ppm for pool) right? On second thought, maybe not since winter is coming, so I don't really need as much salt - until I open the pool for the next swim season.

Does your pool water stay warm enough for your SWG to run year round?

I would use your K-1766 salt reading of 3400+ to decide if you should add salt. Your SWG performance is based on the actual salt level in the pool, which the 1766 better measures, then the questionable salt sensor cell measurement.

To me your salt is at 3400+ now, not 3100.

 

[cflannagan]

Does your pool water stay warm enough for your SWG to run year round?

I would use your K-1766 salt reading of 3400+ to decide if you should add salt. Your SWG performance is based on the actual salt level in the pool, which the 1766 better measures, then the questionable salt sensor cell measurement.

To me your salt is at 3400+ now, not 3100.

Sounds good - I can work with that mindset. Thanks for the help!

Re: staying warm year-around. Well, I'm in Tampa Bay area. So sort of, I think. Water can get as cold as 60 degrees (I'm estimating), but the average air temperature (again estimating) is 75-80ish going through the winter, with some "cold spell" days. I try to maintain my pool chemical-wise year-around (maintaining CYA, TA, salt level, etc).

 

[Oceansol]

Hmmm... What is the lowest temp for water to run the SWCG?

 

[Divin Dave]

About 50F.

Hmmm... What is the lowest temp for water to run the SWCG?

 

[Oceansol]

OK, good. my pool at coldest is about 60F, so I should be good.

Thanks!