Liquid chlorine line blockages

[hale1986]

Good morning,

I have an automatic dosing system for pH (sulphuric acid) and sanitizer (Liquid chlorine/Sodium hypochlorite 150g/litre).

I keep having blockages in my chlorine line, due to white crystals forming primarily around the saddle clamp where the chlorine line meets the pool return line, but have also seen it in the plastic tubing itself.

Its frustrating because the first tell that there is a blockage is when my FC is already low with the feed pump running. If it goes unnoticed I've seen it blow the plastic tubing.

Does anyone else have this problem and know the root cause?

At the moment I've just been clearing the blockage with a screw driver, but perhaps I'd buy more time with a deeper clean. I was worried about soaking the fittings in an acid for example in case chlorine was let off.

Any ideas? Or any other info required?

Thanks

 

[DrewLG]

It's salt and calcium scale. A diluted 10:1 solution of water and MA will clear it.

 

[PoolStored]

I typically clean my lines once a year when I close the pool. I do as @DrewLG indicated. Diluted muriatic will clear all the salts. I also clean out the tank once a year, it also builds salts, primarily on the pickup. I do not use Muriatic for the tank, I flush thoroughly with water in the drive, then when clear, I shop vac out any remaining water and particulates. I feel I can clear any MA from the lines, I don't want to put chlorine back in the tank with any MA in there...

 

[pjt]

sulphuric acid

Do you have access to muriatic acid in Spain? It's preferred over sulphuric acid.

 

[PoolStored]

Do you have access to muriatic acid in Spain? It's preferred over sulphuric acid.

Muriatic acid in Spain is "Agua Fuerte," typically available in grocery stores.

 

[hale1986]

Thanks for the responses!
I'll try to schedule a thorough clean soon to try it out. I have a feeling its also clogged up my non return valve which means it doesnt sit in the closed position very well anymore. Good idea with the feed tank as well, I only installed a tank last year, and although I had this issue before then, it does seem to be getting more regular.

Yip we can get muriatic acid, as PoolStored said, aqua fuerte, or there is a brand called Salfuman but typically this is small bottles. My pool store do sell a Muriatic acid based pH reducer though, I'm not sure why we've always bought sulphuric, why is muriatic preferable?

 

[PoolStored]

Safer. Sulfuric acid also adds sulphates. No bueno para la piscina. Breaks down concrete/plaster, corrodes metals.

 

[hale1986]

Safer. Sulfuric acid also adds sulphates. No bueno para la piscina. Breaks down concrete/plaster, corrodes metals.

Interesting, makes you wonder why they'd sell it? But then again in Spain, lots of things happen just because they've always been done that way .

I'll add this to my big list of things I need to consider changing!