Salt generator not making enough chlorine

Zindar

0
Jun 4, 2011
209
Austin, Texas
I have a Intex Krystal Clear Saltwater System® Model CS8110, which just purchased (and installed myself) in the middle of swimming season last year. I had it turned off during the winter, but when I started it up in the spring, it seems like it wasn't generating any chlorine.

The salt levels are right at 3000 ppm, which is perfect, so that's not it. I did have a bad algae problem, but I've since then SLAMmed, and the water is fine now. I did recently try increasing the hours. I think I used to run it 1-2 hours a day, which was enough to maintain my chlorine level. (Right now I'm using chlorine bleach until I can get the generator working again.)

I just tried increasing to 5 hours a day, and I'm suspecting it's probably generating some chlorine. In 3.5 days, my chlorine levels dropped from 9 ppm to 5 ppm, but I feel like that's less of a drop than I'd've had with no salt generator, so I suspect it's making some chlorine. Furthermore, I can see gas bubbles forming near the cell, which I suspect are chlorine gas.

I just consulted the troubleshooting tips of my manual under the problem of "insufficient chlorine":

• Insufficient operating hours of
the Saltwater System.
• The salt level in the pool water
is less than 2000ppm. This is
insufficient.
• Chlorine loss due to intense
sunlight exposure.
• The bather load has increased.
• Clogged or dirty electrolytic cell.

I think I can rule out all but the last one. For that last one, it says: Remove the cell for inspection, clean it if necessary. See “Maintenance”.

:eek: I confess I've never done this. The manual says to inspect it monthly. :eek: It further says "The electrolytic cell (6) has a self cleaning function incorporated into the electronic control's programming. In most cases this self cleaning action will keep the cell working at optimum efficiency. If the pool water is hard (high mineral content) the cell may require periodic manual cleaning."

I don't think my water is extremely hard, and actually it was freshly filled last year (because that's when the pool was built) from a water truck using Austin municipal water, which is not hard, but I've added water countless times from my hose due to evaporation, backwashing, and one unfortunate episode when I accidentally siphoned out maybe 1/6 of the pool. My house water is hard enough that I have a water softener, so I suppose this could be the culprit.

Therefore, this weekend I plan on the cell inspection and cleaning. The instructions say to plug up either end of the housing (using something called a cell cover) so that I can fill it up with vinegar. I hope I have the cover they speak of; I don't remember seeing it. Still, if it came with the generator, I doubt I would have thrown it out.

Oh well, I guess I don't really have a question at this point, as I think I know what I need to do. I hope soaking the plates with vinegar is all that's needed to resurrect it. And I hope I have this cell cover they speak of.
 
Zin, if you have an algae problem or had an algae problem with a SWG something is definitely wrong. I'm no expert but 1 or 2 hours a day of pump run time seems to be inefficient. What percentage do you have the setting at ??? 30%, 50% 100% ??? Also, what is your CYA currently at ??? How are you testing your levels ??? You should post your water balance numbers so the experts can zero in on what exactly is going on. Just some thoughts here.
 
If you're seeing bubbles at the cell, it's most likely producing. I'd make sure that you don't have a nascent algae bloom and that your CYA level is correct.

It would be nice if you'd post a full set of test results and how you got them. It'd also be nice if you told us the process you used to determine that the water is 'fine' now.
 
Zin, if you have an algae problem or had an algae problem with a SWG something is definitely wrong. I'm no expert but 1 or 2 hours a day of pump run time seems to be inefficient.
My model of SWG only runs at 100%, so you control the chlorine by the generating time, hence my setting at 1 to 2 hours a day.

I pump the water for more hours than that, but that's how long the generator used to generate per day.

As for the algae, here's why it happened. As I've had my pool less than a year, I was unprepared for the massive dumping of leaves into my pool that happened last fall. The leaves overwhelmed the skimmer basket, and so I actually shut off my pump until I could get the leaves out. I went through a medly of strategies, until I finally figure out how to get all the leaves out. In the end, I am now the owner of two new devices:

1) a "Wanda the Whale" automatic vacuum, with optional leaf basket, which works great, but only when there's a moderate amount of debris. For when there are massive amounts of leaves, I now use

2) a Blue Wave NA316 Leaf Bagger
71tSepn-cML._SY355_.jpg


By the time I got my water clean, I had developed the algae problem, since the pump and SWG weren't running.

I also speculate that since the water was not circulating, I wonder if that somehow promoted mineral buildup on the cell plates in the SWG.

- - - Updated - - -

+1 what bama said

Okay, this weekend I'll do a full water test using my TF-100 kit. (I think those of the letters on it, if I remember correctly.)

As for CYA, it's been several weeks since I measured it, but I think it's 70 or 80. I always have a hard time accurately measuring CYA, because it's hard to tell when that black dot has actually disappeared.
 
While the pump was off, a good plan would have been to use bleach to maintain adequate FC. And not having the SWG running would not have caused any build up on the plates.

A SWG will not eradicate algae. To do that you need to follow the ShockLevelAndMAINTAIN Process.

I will repeat: What are your test results and what test kit are you using?
 
Have you checked to see if your voltage is within operating limits, your transformer may be malfunctioning so no matter how much you are running through the cell it's not being powered. I would also take it apart and look at the fins for any hard water build up or clog/damaged fin
 
While the pump was off, a good plan would have been to use bleach to maintain adequate FC. And not having the SWG running would not have caused any build up on the plates.

A SWG will not eradicate algae. To do that you need to follow the ShockLevelAndMAINTAIN Process.

I will repeat: What are your test results and what test kit are you using?

Isn't it a bad idea to add bleach with the pump off though?

Also, as I said, i did perform the SLAM and the algae is gone now.

My test kit is the TF-100 Test Kit, in the next few days I should be able to run a complete test. Possibly tonight after my son's track practice I might get a chance, but probably not because I think I need sunlight to do the CYA test.

As of a few weeks ago, I think my CYA was 70 or 80, and my CC level was .5 ppm, but I realize those are just incomplete results.

- - - Updated - - -

Have you checked to see if your voltage is within operating limits, your transformer may be malfunctioning so no matter how much you are running through the cell it's not being powered. I would also take it apart and look at the fins for any hard water build up or clog/damaged fin

I don't have a voltmeter; I suppose I could get one if needed, but first maybe I should follow the instructions for inspecting for minerals and soaking in vinegar if I see any. Then if it still doesn't work, maybe a voltmeter purchase might be in order.
 
It was roughly a month ago, and I've been manually bleaching since then, the water is still crystal clear, and my CC has been staying under .5 ppm as the criteria require. But I'll soon do another complete test to verify the water is still in good shape.
 

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Okay, I just did a complete test, but it was after the sun was low in the sky, so I wasn't in directly sunlight when I did it:

FC = 5.0
CC = 0.5
PH = 7.55
CYA = 65
ALK = 105
CH = 130

For the CYA, I wasn't sure, but at 70 I thought a saw that general area where the black dot was supposed to be was a bit fuzzier than the surrounding water, and at 65 I'm pretty sure even that fuzziness was gone. If so, my CYA is a bit lower than normal. If needed, I could raise it by adding one of my chlorine tabs to the pool.

The remarkable finding is that in the last 2.5 days, my FC has held steady at 5.0, even though I've not added any bleach. My salt generator must be working. Still, it's running 5 hours a day, which is 3 times longer than it had to run last season for the same amount of chlorine generation, so I feel like it's not working as well as before.

So, I think this weekend I should inspect the plates for deposits. Another thing: Last season I hard plumbed my pool, so I can't put the cell cover on as the manual says. I do have unions installed very close to each end of the SWG, so maybe I can find some threaded caps at home depot I could use to seal off the two ends as I fill with vinegar.

Question: at my last house, I was told not to use vinegar, but muriatic acid to clean off the plates. In general, do you think that would be acceptable in lieu of vinegar on my current SWG, even though the manual says to use vinegar? I just ask because I can buy muriatic acid by the gallon, but vinegar comes in little bottles at the grocery store, and it's possible that acid might be cheaper per unit volume (but I confess I could be wrong about that - maybe it's not.)
 
The cover referred to in the manual is a screw on cover to screw onto one end of the chlorine cell. Put that cover on one end, stand it on that end and fill it with vinegar. Muriatic acid is fine too, but it does not take much to fill the cell. I would use what is recommended in the manual.

There are two likely reasons why the SWG seems to be making less chlorine than last year. 1, there is build up on the cell plates or 2, there is a low level of algae in the pool consuming the chlorine.
 
That's a handy tip about standing it on one end, so I only need one cover. Both ends are threaded, and I actually have threaded PVC on there right now, held with thread sealant. Just beyond is a union. That's why I'm thinking of getting a threaded cap to put on the union to get the job done: otherwise I'll need to remove the PVC and reinstall when I'm done.
 
You could use a union half that's capped off.
If you're not used to using muriatic acid, it's a very strong irritant. I'd stick with vinegar and if that doesn't produce the desired results, then I'd dilute some HCl and try it.
 
I looked more closely today (I didn't have time to to the actual work, as I was at my son's track meet most of today), and I now think I can get this done without buying a union cap.

Not only do I have a union (that I installed) very near both ends of the cell, but right after the the union on the titanium plate side of the SWG, about 12 inches from the SWG itself, I have an elbow joint and halfway up the next PVC segment another union. So I could disconnect the second union, and aim that segment of pipe upwards, so that the vinegar can't spill of the SWG. :)

Tomorrow I plan on going to the store and buying some vinegar. One thing is: it's hard to inspect the plates inside the SWG because they're not easily visible. I can open the cap where the copper electrodes are, and just a few inches down the pipe from there are the plates, but I can't get a good direct look at them. Maybe it's simpler to just treat them with vinegar, and if they need the treatment, job done, and if they don't, no real harm done.
 
I'm about to go do the work, and I wanted to say I have respect for what vinegar can do. I once had mineral deposits on a master bathroom shower cartridge filter, and I struggled for the longest time trying to remove it, even breaking a tool in the process. Then a CSR from Moen suggested to me that I wrap a vinegar soaked rag around the filter and leave it there an hour or two. Like magic, that did the trick.

Amusingly a couple years later the same thing happened to my next door neighbor, but he hired a professional plumber rather than fixing it himself. His plumber struggled supremely and spent a lot of billable time in his struggles, but apparently didn't know about the vinegar trick. You'd think a professional in the business would know better, and here I am, a total novice, who realized I should call the manufacturer for advice (and got it - Moen customer service is very helpful.)
 

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