Switch concrete IG to Salt? Why I hesitate...

[dking]

We can't decide if it's wise to convert our concrete IG pool to salt/SWG (Ontario Canada). It's our second pool and it's not open yet.

First, I wanted to just say hi...I just joined the forum the other day after spending many hours reading about SWG and some long "discussions" about the good and bad of salt residue and possible corrosion of stone and tile above the waterline.

Any thoughts about the tiles/grout (stone and concrete too) specifically if we convert to salt water?

I'm proceeding with caution - I want to do my homework on this before I shell out for a SWG.

Here's pictures taken last fall before we got the house (the pool was closed when we moved in).
DSC_9194-pool.jpg
DSC_9196-pool.jpg
DSC_9199-poolsteps.jpg

and some other background...

Previous pool experience (what is this a resume? :? )
Our first pool was a new 15 foot diameter AG resin pool w/ a SWG. My father and I installed it ourselves (he lives far away and never got to swim in it, so I get reminded of this now and again).

We loved it and so did our two girls! It was easy to look after and I liked the SWG. We had it for 2 years, so that's the extent of my pool experience. It was easy to balance 18,000L (yup we're in Canada - near Toronto).

Now we have a concrete IG pool :-D
We moved last fall and now we've graduated to a 25,000gal (95,000L) concrete IG pool probably built in the 70s. The pool has no automatic chorinator, just pump, sand filter, and gas heater.

We budgeted to install a SWG (and possible a new heater) since we have experience running a salt pool and everyone loves the "salt pool feel".

The heater is old, so our local pool shop warned us that salt will likely accelerate the corrosion of the clunky old heater. This triggered me to do some other research which led me here.

To convert to salt or not?
I was going to install a SWG before we open in the next couple weeks, but now I'm not as sure. We are hesitating now on the SWG because we're not sure what the long term effects might be on the tile above the waterline and stone around the pool. (I don't know what kind of stone it is yet)

We want to take good care of the pool and avoid costly repairs in the future.

I'm guessing that we won't be diligent at washing down the tile and stone either...we'll try since I hear it is good practice regardless, but we're busy to say the least.

Again, thoughts about the tiles and grout specifically if we had salt water?

We're still leaning to salt, but I'm sure we'd enjoy a well balanced pool without it too. Sometimes it's best not to fix what's been working.

Thanks!
-Dennis

 

[PoolGuyNJ]

The existing coping and deck are fine with salt. I do strongly urge you seal the expansion joint between the deck and the coping. This will keep water out from behind the pool, prevent wicking by the mortar and result in freeze damages to the coping and tile.

Check for continuity between the ladder and the house ground rod outside by the electric meter. If it's good, the ladder is safe from electrolysis related corrosion.

Check the bolts holding the dive stand for continuity too. If it's good, paint them with a vinyl coating.

If either is not bonded to the ground loop, pass on the salt cell.

An old heater is an old heater. It's going to break sooner rather than later anyway and if it's been obsoleted, as happens with old heaters, will be better to invest in a new heater than to start the fix, find parts spend, fix, find parts, spend, cycle.

If everything is bonded, adding a bonded sacrificial zinc anode after the salt cell will create an additional layer of protection against stray current related electrolysis corrosion.

Scott.

 

[dking]

Thanks!

I'll do some grounding checks... Is the lack of proper grounding the primary factor for avoiding a salt system for a pool like ours? If that's the case it does give us something to base a decision on. (since we're looking to avoid any possible long term side effects)

As for the heater, ya we budgeted assuming we may have to replace it since it's fairly old. If we don't buy a SWG then we could replace the heater now and gain some efficiency of a newer model.

Sealing between the coping and deck sounds wise. What are options to do this? I'm learning...I'll do some searching - probably other threads talking about it somewhere.

-Dennis

 

[dking]

There is ground continuity from both the ladder mounts in the deck and the dive board bolts to the ground wires coming in at the electrical panel in the house.

(there is a pool light under the dive board too). There's only tiny scrapes of bare metal on the edges of the bolts.

Good news I suppose! ...either way

 

[JasonLion]

Where do you live? If you live in an area with reasonable amounts of rainfall and high humidity in the summer, then you should be fine. If you live in an area with very low rainfall and low humidity, I would think more about how much stone work is right near the water and what kind of stone it is. One good test with stone is to pour a little water into a hollow spot on the stone and see if it gets absorbed into the stone. If it is absorbed within a couple of minutes and the stone will get splashed on then you probably have a problem.

The tile/grout will be fine with salt water.

Checking the ground continuity is always a good idea, but it really ought to be right already.

 

[PoolGuyNJ]

Deck-O-Seal has a high quality, self leveling caulk for the expansion joint.

here's the link: http://www.deckoseal.com/

Scott

 

[dking]

Where do you live? If you live in an area with reasonable amounts of rainfall and high humidity in the summer, then you should be fine. If you live in an area with very low rainfall and low humidity, I would think more about how much stone work is right near the water and what kind of stone it is.

Thanks. Looks like another point in our favour that might help us lean towards salt. There's usually humidity in the summer since we are close to the great lakes. I'll check the stone like you suggested tomorrow if I can.

Toronto area - from wikipedia
Maximum temperatures typically range from 23 to 31 °C (73 to 88 °F) with moderate to high humidity, onshore winds from Lake Ontario contribute to summer moisture content but far away sources like the Gulf of Mexico also factor in. Temperatures 32 °C (90 °F) or higher do occur but are rarely prolonged and in exceptional cases it breaches 38 °C (100 °F). Summer heat episodes are usually broken by cooler, drier periods not experienced further south on the continent.