Salt Pool Chlorine Generator-silly Idea

[mwhitnell]

Ok....here goes

I just converted my pool to a 3000ppm saltwater pool( something I am allowing to change over time thru backwash and makeup thus eventually a fresh water pool). This analysis explains that a salt cell is not cost effective and reliable.

I use approx 1 gal chorine a week. My pool is useable about 5 months a year, and dormant the remainder. Chlorine cost $2.00/gal or $40 per 5 months and maybe the same to carry to pool thru the dormant months...so a tota of $80/yr for chlorine. A chlorine cell cost $1000 + or -, the cell lifetime is 5 yrs. A replacement cell is approx $500,,,so that is an expendable cost of $100/yr,,,,you just lost $20/yr not to mention the cost of $1000 initial for perhaps a lifetime cost of $100/yr for 10 years, therefore you just spent $120/yr over and above the cost of liquid chlorine.

From purely a cost standpoint a salt chlorine generator is a stupid idea,,,not to mention that reliability is poor,,,most everyone who has one has had their pool turn green.

So dont buy a chlorine generator, go the Pinch A Penny and buy your liquid chlorine. And dont try to keep the level ppm so close that it is borderline, thus causing you to get a green pool if you dont check it regularly...over chlorinate.

[chem geek]

The cost analysis will vary depending on the pool, but with the lower prices for SWG systems these days they are getting more economical for many pools. It is true that for smaller pools with shorter seasons and therefore lower chlorine usage, the manual dosing with chlorinating liquid or 6% unscented bleach is often more economical. This is the case with my own pool even though it's 16,000 gallons with a 7-month swim season because it has an opaque electric safety cover so that my chlorine usage is only 1 ppm FC. I use 12.5% chlorinating liquid that I get from my pool store (who reuse the bottles) at $3.65 per gallon so that's about $14 per month or around $100 per year.

There are SWG systems whose cell replacement cost approaches $300 and cells are starting to last longer (they used to last more like 3 years and are now lasting closer to 5 years). Nevertheless, the primary reason people buy an SWG system is for the convenience.

Most people with SWG systems like them and most do not have their pool turn green -- at least from reading reports on pool forums. Some people think they can forget pool maintenance with an SWG pool and that's not true so those pools are more likely to have problems. The biggest issue with SWG pools is the tendency for the pH to rise, but this problem is reduced by lowering the TA level and in some cases by also using 50 ppm Borates in the pool. There are also potential corrosion issues due to the higher salt levels, but these can be mitigated (unless, for example, one has soft limestone coping and is unwilling to seal it).

For any pool, manually dosed or an SWG pool, the key to preventing algae using chlorine alone is to make sure that the Free Chlorine (FC) level is appropriate for the Cyanuric Acid (CYA) level. For a manually dosed pool, algae can be prevented if the FC is never below 7.5% of the CYA level. For most SWG pools, they stop algae when the FC is never below 5% of the CYA level. The 1-3 ppm FC with 60-80 ppm CYA recommended by most SWG manufacturers is not enough to prevent algae. The 1-2 ppm FC is simply not enough. 3-4 ppm FC will work as this is 5% of the 60-80 ppm CYA level.

Richard

[Strannik]

mwhitnel, here is another case study for you:

I just had a guy contact me for a quote on SWG for his 475509 gallon pool.

He currently uses 265 gallons of bleach per week.

Now with the prices you've mentioned he will spend $138300 on bleach within next 5 years.

Suitable SWG will cost him around $59000, with the replacement cells costing 25000 for a set of 2. Electricity will cost him around 20k.

Now if we do a quick calc we'll see that over 5 years he will save 35k. Not bad, eh?

More so, because we are counting the price of cells we need to extend that period to 10 years.

So we get 270k for bleach, 40k for electricity, and let's say 20k for maintenance. 270k - 145k = 125k savings over 10 years.

Oh and the prices for equipment i've mentioned are retail, so obviously actual price will be lower. Plus for pools this big you don't pour bleach manually, you need dosing equipment, which adds to the cost of bleach.

Kinda hard to call it not cost effective

With regards to reliability it's simple - don't go cheapest route when buying one. I can assure you that there is much bigger quantity of green pools which never had SWG, than those with SWG.

[lancef1]

I will have to agree with the responses from spa guru and spa savant. A good chlorine generation system properly installed and maintained has been one of the best alternatives to packaged chlorine I have ever experienced. Having made over 13,000 service calls on hot tubs to 1.8 million gallon facilities in the last 23 years, I have seen all kinds of things come and go and come and go again.

The single common demominator in the problem pools I have seen is Tri-Chlor tablets. I have seen more destruction and poor water quality from this option than anything else. People get it because it is cheap and the dispensers are cheap - at least when you first buy them. The only problems I have seen with chlorine generation are undersizing units because someone was trying to be cheap, lack of understanding on how the units work, no understanding of water chemistry or just plain laziness. Chlorine generation is not a magic wand but if you follow the rules it will provide convenience, time, long term savings and exceptional water quality. I have installed many different brands and only one of them dissapointed me and have not had one customer ever be dissapointed with their water quality. In fact, I still still many of them that thank me after several years of having one.

If you want to get one make sure you don't go out on price or you will most likely be dissapointed. The bargain basement ones usually go out of business after 2-3 years and offer no real tech support. Quality and support cost money so if you are pinching pennies, go ahead and get nickled and dimed buying a little chlorine here and there.

If anyone is looking for a good hot tub system, I know of 2 - the ColorChlor and Spa Pilot. Compare them and see which one suits your taste.

Lance

[demfourlife]

The salt pool chlorine generator system is the way to go. I use to have a hard time keeping up with my pool, dealing with the wife's complaints. Now the pool pretty much cleans itself provided you have enough salt in it (usually 2 bags every 6 months).

I have a blog that is related to the salt chlorine generator system. You can visit it at:

http://saltpoolchlorinegenerator.blogspot.com/

If I can help you with any questions, please email me. Good luck.

[floater]

In my part of North Carolina we have soft water and no liqiud chlorine (i kno, everyone has bleach. lol). so we use cal-hypo and we use tri-chlor tabs. for a 18x36, 20x40 pool we're talking a bucket of tabs ($100) and a bucket of cal-hypo ($100) per year. so two hundo a year, while a grand for the start up of a SWG might seem expinsive, and $500 dollars every 5 years! might sound like alot, do the math. muriatic acid is basically as cheap as bicarb, so the switch is pretty simple.