Struggling with Salt Water Generator (Zero FAC)

[Rowewar]

Hello, I'm new to this site and looking for some help.

I have a 30ft round pool (~23000 gal) and am using a Compupool salt water chlorinator (don't get me started with the list of issues we've had with it). Compupool has replaced the cell once, and has said they will replace it again (with the issues we are having) but we have been waiting over 6 months for 'stock' which they have none. I'm not holding my breath on this and am pretty sure we are stuck with what we have:
"Mr Millar’s company Compu Pool, which manufactures and imports swimming pool equipment, was put into liquidation in June 2014 but the liquidator left in August last year and the business was still in operation yesterday."

My chemistry is good, and I can see what I believe is chlorine being generated by the cell, yet everytime I test the water I have zero FAC. It becomes a battle to shock (in the meantime) to keep things clear, while trying to figure out this generator. I've added more than enough salt, bumped the output to 100%, anything I can find in the manual to get either the test strip to show ANY FAC, or the pool store to give me an answer other than 0.

My questions are:
1) Any other suggestions to get FAC residuals?
2) What should I be doing as a 'keep it clear and swimmable' while I figure this out? I have been shocking, but the zero chlorine pool is constantly fighting me back...

Latest water chemistry:
FAC: ZERO
Alkalinity: 120ppm
Calcium Hardness: 220ppm
Stabilizer: 50ppm
Phosphates: 100ppm

Thanks!

 

[Subscribe1028]

Salt level?

 

[Griswald]

What are you using to test?

 

[Rowewar]

So my salt level was at 2700ppm two weeks ago. I've added 5 40lb bags since so according to the charts, I should be ok there. I haven't found a good DIY salt tester, any recommendations? I've been bringing samples in to my local Leslie pool store.

 

[ping]

Welcome to TFP!

You need to start off by adding liquid chlorine to raise the FC to 5ppm which should be about a gallon of 12.5% strength chlorine. You should maintain with liquid chlorine until we solve the SWG issue.

A pool can have clear looking water and still have enough organics in the water that consumes the chlorine as fast as a SWG can make it. This is very common with pools that have SWG's and the best method to determine if there are organics in the water is to run an OCLT, Pool School - Perform the Overnight FC Loss Test (OCLT).

To do this test you will need a test kit that has FAS/DPD test for chlorine. I recommend the TF-100, see my signature for test kits.

We like to troubleshoot pools with accurate test numbers and pool stores often don't have reliable numbers.

The Taylor K-1766 test is the best kit for residential salinity tests. It can be found at tftestkits.net.

 

[Rowewar]

Thanks for the advice Ping! First I had seen of these test kits and it makes a lot of sense to get a handle on the testing myself.

I'll run through the OCLT tonight, but until the kit arrives, I'll be using test strips. Will maintain with liquid chlorine for now.

 

[kcindc]

Which kit did you order? You can't do an OCLT with test strips because they are not accurate enough.

 

[Rowewar]

Understood kc, I ordered K-2006 and K-1766. I know (now) you need FAS-DPD to run the OCLT. My strips (which were never registering any FAC) are finally showing some purple daily, somewhere around 1.5. Looking forward to receiving the kit so I can get some more accurate numbers. How often do you guys recommend running the OCLT test and the FAS-DPD in general?

 

[kcindc]

Some folks never have to run an OCLT. Our methods help you keep your pool clear so you never have to SLAM.

Here is a pool school article on the basics... your pool and its needs will vary. I have to empty my skimmers a few times a week, but some folks with pool cages can go longer. The key is understanding what you pools needs and only doing what is necessary to keep the pool clean.
Pool School - Basic Pool Care Schedule

While you wait, read as many articles in pool school as you can and check out Pool Math. The learning curve is steep, but ask questions and soon you'll be a TFP pool snob. Post up your first set of results and we'll walk you through the rest.

 

[ping]

The OCLT is only done when the chlorine usage is high for some reason, so it is rarely needed. It is a troubleshooting test to determine if organics are causing a higher demand of chlorine.

I use the FAS/DPD test every time when I check the FC. Once you dial in your pool and understand its characteristics, you will most likely only need to check the FC twice a week since you have a SWG.