auto fill

[morning dipper]

Hello,
at the design stage for a newbuild inground concrete pool about 50,000litres, with SWG.
Previous pool had an auto fill system which used a redundant sprinkler zone feed, rerouted to squirt water into the pool from pool house roof. Air delivery.
A few minutes a day was usually sufficient to top up and the squirty jet was a bit of a feature.
Another aspect was that pool water and mains water were never in direct contact.......useful or irrelevant?
My question is how important is it to keep pool water and mains water separate, I'm thinking electrical earth leaks, electrolysis, or other parasitic electrical issues.
New build has a different layout and it's difficult to fill by air delivery, so might need to plumb direct into a line somewhere.
Any issues with that (plumb direct) or is that pretty much standard practice.
Any thoughts most welcome.
Thanks for listening

 

[HermanTX]

In the USA, all external faucets (for hoses, etc) must have a backflow preventer. This keeps any backflow from entering the home water supply. Check your regulations in France for similar requirements.

If it is connected to the sprinkler line directly, probably not much of an issue if the sprinkler is independent of your home water supply or it has the backflow preventer on it.

 

[ajw22]

An air gap is an important safety feature to separate potable water from non-drinkable pool water and prevent contamination of water supplies. Your air delivery is a simple way to achieve that.

Otherwise a Back Flow Preventer - Further Reading needs to be used to protect water supplies if directly connected.

 

[morning dipper]

Thanks for replies, yep backflows and avoiding possible water contaminations will be taken care of, but my 'worry' is about rogue electrical currents and metal fatigue via galvanic action. Is that an issue in pools/connected houses via a water link.
Perhaps a pvc pipe and pvc backflow valve will give sufficient electrical insulation, except when the valve is flowing open!

 

[ajw22]

Thanks for replies, yep backflows and avoiding possible water contaminations will be taken care of, but my 'worry' is about rogue electrical currents and metal fatigue via galvanic action. Is that an issue in pools/connected houses via a water link.
Perhaps a pvc pipe and pvc backflow valve will give sufficient electrical insulation, except when the valve is flowing open!

No.

Rogue electrical currents from what?

Pool plumbing is not different then your house plumbing and will not introduce any new problems.

 

[morning dipper]

Reading around I found some threads on galvanic action, and my reading of this (for pools anyway) was for peace of mind install some zinc anodes, but generally galvanic action in pools was pretty insignificant.
With a water link to a house with more metal (taps and fittings and washing machines etc) galvanic action might be more of an issue.

 

[ajw22]

Reading around I found some threads on galvanic action, and my reading of this (for pools anyway) was for peace of mind install some zinc anodes, but generally galvanic action in pools was pretty insignificant.
With a water link to a house with more metal (taps and fittings and washing machines etc) galvanic action might be more of an issue.

It is not an issue.

 

[morning dipper]

No.

Rogue electrical currents from what?

Pool plumbing is not different then your house plumbing and will not introduce any new problems.

well that's what i'm trying to establish (rogue currents). SWG maybe, salt water, dissimilar metals - if not in the pool my house has aluminium and copper and steel and all sorts in the water system.
I'm a boat man and I know salt water and different metals causes problems, and i'm trying to work out if plumbing my house water into my pool water i'm going to get any problems down the line......

 

[ajw22]

well that's what i'm trying to establish (rogue currents). SWG maybe, salt water, dissimilar metals - if not in the pool my house has aluminium and copper and steel and all sorts in the water system.
I'm a boat man and I know salt water and different metals causes problems, and i'm trying to work out if plumbing my house water into my pool water i'm going to get any problems down the line......

Ocean salt water is 30,000 ppm of salt. Pool salt water is 3,000-4,000 ppm of salt.

Your house and pool is not a boat in the ocean.

 

[HermanTX]

and my reading of this (for pools anyway) was for peace of mind install some zinc anodes, but generally galvanic action in pools was pretty insignificant.

Zinc Anode for Salt Water Pools, is that recommended?

there will be a competitor that will have less onerous restrictions on their heater that will make its lifecycle costs cheaper and service companies will be happier to service those heaters as it’s less involved. Most service companies decide which heater gets installed and most have a...

www.troublefreepool.com

There is a lot of good info from very respected experts on use of anodes. Do what you need to for peace of mind but generally an anode is not required.

 

[morning dipper]

thanks all for your input

 

[newdude]

I'm anti anode. They serve a specific purpose when dissimilar metals are touching, which doesn't apply to pools. This part over here and that part 25 ft away won't be helped. Or, they need to be 1% to 2% of the metal they are meant to protect, in close proximity.

Take steel walled pools for example. For one, the water never touches the wall on the other side of the liner, and if it does, the moisture will cause catastrophic damage either way. But *if* they were to help, you'd need an appropriatly sized chunk on each wall panel. Haphazardly installing a single anode in a random location won't blanket protect the pool and all its equipment.

Your pool light for another example only touches itself and if the material requires an anode, it will come with one attached from the factory. The same with heaters. It's not on you to add anodes where the manufacturer deemed they weren't needed.

But as said above, if the worst you get taken for a ride on your build is $100 anode, you got off easy.