Swimpure plus salt level not indicating properly... anything to check before buying a new cell?

[shorembo]

My swimpure plus is:

• showing 2900 for salt level but I measure between 3400 and 3600
• doesn't seem to be making much chlorine (stabilizer measures fine)
• my current salt cell is over 3 years old
• I did just fix my thermistor on my board (coincidence?)
• the only other time my salt level didn't measure right the problem was the cell

Anything else I need to check or do I just replace the t-15 cell?

I thought about just going ahead and purchasing a replacement. Worse case would be it doesn't fix the issue but I don't think I have ever has a cell last more than 4 years anyways so I will need a cell within a year.

Also... found this from poolsupplyworld ($299). Replacement T-Cell 15 Salt Cell | Pool Supply World

 

[YippeeSkippy]

Ok....you're sized right.... have you checked your cell for calcium build up? Does it need cleaning?

I never trust a device to tell me my salt level, instead I only trust my K-1766 Salt test kit. K-1766 Taylor Salt Test

Call your local pool store and ask if they can test your brand of cell?

Is there a chance your pool may have a nascent algae infection which is chewing thru your FC?? Try an Overnight Chlorine Loss Test to check that out- Overnight Chlorine Loss Test

Another check is to use a plastic cup and run it up the wall of your pool empty up to the return and capture the water coming directly out of the return while your SWG is producing. Test that, and it should test higher in FC than the rest of the pool.

Just some ideas....

Maddie

 

[shorembo]

Thanks for the feedback....

I have a the home test kits and run my own tests. My salt test result is now different than what the SWG is saying and this usually means trouble.

Anyways...
I tested overnight and there was no drop of chlorine.
And, I tested the jet output water versus regular water and didn't see much difference (3ppm each test).

I seem to be hovering around 3ppm even with the generator on 10 hours.

I ordered the cell just in case.... 20 years of experience means I know I will eventually need one. I may mess around with the calibration but that just seems like delaying the inevitable.

 

[mknauss]

I am surprised your cells only last that amount of time. Have these all been non-Hayward cells? Many 'lower price' off brand cells have fewer generating hours worth of life. So be ware of that.

 

[shorembo]

Thanks for the feedback...
I have had my pool 19 years and probably have had 5 cells. I think the shortest length was just less than 3 years while MAYBE the longest was 5 years usage. I think my first two were Hayward then I went with OEM.

If I am supposed to get more length, I can think of a few reasons I am not.
1. Florida - somethings just don't last long in Florida... lots of sunshine and usage year-round.
2. Outdoor / uncovered pool with plenty of vegetation - probably not an issue but there have been times the cell has had stuff in it
3. User Error - definitely possible... whether cleaning or I have it set to 70% production almost all the time or I boost my pool with liquid chlorine or don't really use any chems beyond acid, liquid chlorine, and stabilizer.

Anecdotally, I have noticed that for the last 10 years I hardly have any blue/white deposits on my cells. This use to always occur but I can't remember the last time it has happened and I have been using OEM cells for the last 10+ years.

 

[mguzzy]

BLUE! what the heck is that.. I have only ever seen white deposits (calcium) ... The only time I see blue in pool stuff is when copper is involved or when my solar cover is coming apart. hmmm.
Yeah.. running a SWG 70% of Full blast year round will use them up faster. If your local store can test the cell for you, do that. there is a simple procedure for testing if a cell is pooping out ... and I can never remember it so I am calling the guy that does.. @JamesW

 

[JamesW]

For AquaRite, move the switch from auto to off and check all of the readings.

Move the switch back to auto and recheck the readings.

Move the switch to off for a minute and then back to auto and recheck the readings.

Report all readings.

What are the first seven characters of the cell and box serial numbers?

What is the actual salinity and how are you measuring it?

What is the T-cell size?

Is the T-cell size set correctly in settings?

To get the performance percentage of the cell, divide the instant salinity reading by the actual salinity reading.

You need to be really sure about the actual salinity reading.

You need to use a K-1766 salt test kit or a calibrated meter.

 

[mguzzy]

To get the performance percentage of the cell, divide the instant salinity reading by the actual salinity reading.

I should really bookmark this procedure so I don't have to keep bugging you.. if this performance percentage is below 75% its "new cell time" (when combined with the other info)... right? That's what I recall from previous posts

 

[JamesW]

if this performance percentage is below 75% its "new cell time"

Correct.

You also need to look at the instant salinity in both polarities to see if they are close.

 

[shorembo]

When I say blue stuff it is white deposits that seem to have a slightly blue tinge.

I tested: (NOTE this is a SwimPure+)

switch from auto to off and check all of the readings	Move the switch back to auto and recheck the readings	Move the switch to off for a minute and then back to auto and recheck the readings
2900	2900	2900
82	82	83
31.4	25.9	24.6
0.00	4.10	5.79
83p	84p	83p
-0	-1600	-2900
AL 1	AL 1	AL 1
r 1.55	r 1.55	r 1.55
- 15	- 15	- 15

Hopefully the above make sense

What are the first seven characters of the cell and box serial numbers?


What is the actual salinity and how are you measuring it?
Salinity tested with K-1766 is 3600
What is the T-cell size?
T-15
Is the T-cell size set correctly in settings?
? I never changed it
To get the performance percentage of the cell, divide the instant salinity reading by the actual salinity reading.
? 2900/3600? Not sure what this will mean
You need to be really sure about the actual salinity reading.

You need to use a K-1766 salt test kit or a calibrated meter.

 

[JamesW]

The instant salinity in one polarity is really low.

I would say that the cell is dead.

 

[JamesW]

When I say blue stuff it is white deposits that seem to have a slightly blue tinge.

The blue is usually copper.

 

[shorembo]

Thanks very much for the answer.

Any tips on making a cell last longer when I get a ton of sun and I run my pool year round? (And I usually supplement with liquid chlorine in the summer)

 

[JamesW]

Any tips on making a cell last longer when I get a ton of sun and I run my pool year round?

Get a genuine Hayward cell.

 

[mknauss]

With a 40K rated SWCG, there should be no reason to supplement with liquid chlorine, ever, unless you are unwilling to run the pump long enough.
Let's assume your pool needs 3 ppm FC average year around. The SWCG would need to run 7 hours per day at 100%. So 2500 hours per year. The Hayward, Pentair, Circupool, etc cells are good for 10000 generating hours. So 4 years.

 

[JamesW]

T-15 = 533 lb chlorine gas lifetime or 362 days at 100% or 8,688 hours at 100%.

T940 Extended life cell = 665 lbs chlorine gas lifetime = 453 days at 100% = 10,860 hours at 100%.

 

[JamesW]

NOTE this is a SwimPure+

It's the same thing as an AquaRite.

Hayward Aquarite SWG - Further Reading

www.troublefreepool.com

 

[shorembo]

Thanks for the numbers on the T-15 ...
So at my general settings: 70% with 12 hours pumping 1/2 year (Summer) and 6 hours pumping 1/2 year (Winter), the cell is over with by 4 years.

As far as burning through chlorine, I have 4 seasons of organics in my uncaged jungle pool (leaves, flowers, pollen, repeat) with high temperatures 1/2 the year (83 right now and 95 for months in the summer).

It now all makes sense.

Eh.... cost of owning a pool.

Thanks again.

 

[mknauss]

You do not maintain your pool water chemistry tests in you shared Poolmath, but I suspect your CYA is too low quite often. And thus you use more FC per day.

 

[mguzzy]

So since you have done this dance before, will have to again I am sure... Did you see how @JamesW got the instant Salinity for each polarity, then compared to your actual Salinity? That is why its important to know your actual Salinity (K-1766) and what the cell thinks its salinity is so you can compare them. So many people find out their SWG is not functioning only after the pool goes green, or they have been adding salt based on what the SWG says and next thing you know you are at 5000ppm salinity and the thermistor blows its top.