Swimming Pools in France

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SWG pool - high chlorine levels

Question for those experts with more knowledge than me regarding salt water chlorine generators.
A pool I have been asked to winterise has an Astral SWG system which seems to work OK, but having visited the pool recently the chlorine levels are very high and the smell of chlorine is very strong around the pool area. Also the vinyl liner has been adversely affected and has wrinkles all over the bottom.
Question is it it possible that the SWG just keeps generating chlorine to achieve such ridiculously high levels ?


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Re: SWG pool - high chlorine levels

It would be a little more helpful to know what the levels are as a high chlorine level doesn't need to give rise to a strong smell unless it's reacting with something.  The SWG should have a probe attached to the pipework to monitor the chlorine level and shut off the unit when the set point is reached.

Wrinkling of the liner is normally due to pH changes outside of the quite wide normal ranges and as SWG cause a rise in pH it could happen.



Passivpool Energy "A++" rated Swimming Pools, the lowest running costs in the Universe.
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Re: SWG pool - high chlorine levels

Thanks teapot. I cant tell the actual chlorine levels as I only use "drops in a tube" type tester, usually good enough for me. The colour of the chlorine side is nearly brown not yellow indicating to me very high chlorine. The pH looks OK and the pH doser reflects the reading ( 6,8)

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Re: SWG pool - high chlorine levels

Ok, try diluting the pool water with the same amount of tap water, take the sample from that and re test but double the result.  You can dilute further if required and multiply the result by the dilution factor.  Oto tests only really show total chlorine and not free chlorine but you'll get some idea of the level.  Any other levels, pH etc would be important too for the liners sake.

Passivpool Energy "A++" rated Swimming Pools, the lowest running costs in the Universe.
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Re: SWG pool - high chlorine levels

OK teapot, understand how to get a more accurate reading of chlorine and the pH as stated is fine at 6,8.
The real question still remains will the SWG keep generating chlorine. The probes are in place in the system and the amperage reading ( the only one on the SWG control box) is at 4 when the instructions state for chlorine generation it should be set at 7
It functioned correctly during the summer period apparently according to the owner.


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Re: SWG pool - high chlorine levels

Is that your pH reading or just from the box as probes do go out of calibration which is why before I commence any work I carry out a full water test.
I would then surmise that it's water under the liner causing the wrinkles, Had a lot of rain your way?

Need to know a salt level as the power maybe struggling at 4 because of a lack of salt and that can cause failure of the power supply unit.  The probe for chlorine should monitor the REDOX potential and when it hits the setting (around 750Mv) it should make the chlorinator shut off. Probes don't last forever and may need cleaning in dilute acid or replacing, when were they last replaced?



Passivpool Energy "A++" rated Swimming Pools, the lowest running costs in the Universe.
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Re: SWG pool - high chlorine levels

The pH reading is both from my test kit and the probe. The probe was calibrated by myself in July using pH7 fluid.

The crinkles in the liner are definitely not caused by water underneath the liner and I am sure are caused by high chlorine levels.

The salt level was fine when tested in the summer (can't remember the level) and the pool has not had a lot of use since then.

I should say that the pool installation and design is frankly awful. Its 10x5m with a flat bottom and just one skimmer and a bottom drain. The two return jets are fed by one 50mm pipe run so not great circulation. The liner fits poorly and has several creases in it running down the sides. When I was asked to open up the pool last July for the non resident owners I met the neighbour who gave me the lowdown on the pool installer who charged the client an exhorbitant price for what they got and all work was carried out at night ! (Black?)
The liner then looked as though a large amount of javel had been poured into the pool from one end as the liner was wrinkled up more on the steps than elsewhere. Since then the timer timings that I set were changed, the water fell below the skimmer and the pump ran dry for a time and the chlorine level has shot up. I think there could be a history that points to a disgruntled individual gaining access to the pool and pump room (its not secure), and its in an isolated setting.
I will be telling the client that I cannot look after it next season and they should find someone else. I cant be doing with the hassle and have better things to do with my time.

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Re: SWG pool - high chlorine levels

Ok understood, the combination of high chlorine and low pH, 6.8 is too low if the chlorine is excesively high could cause wrinkles, what colour is the liner as excesive chlorine will bleach out the colour, any evidence of this?
I have been sent a photo from a proud new pool owner, same size pool as this one, single skimmer and no bottom drain, what could I say? They went on to recommend this pool builder to someone else so I quietly stepped in, no idea if they took any notice.

I know what you mean, this year I have walked away from a pool which requires work to improve it but I got the impression the owner wasn't listening so I am affraid I won't be going back to that one.  Much better use of time on other projects.

Passivpool Energy "A++" rated Swimming Pools, the lowest running costs in the Universe.
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