Salt Pool Problems
I got my feet wet in the pool business in 1975 working with an electronic chlorine generator manufactured by Diamond Shamrock, at that time the third largest chemical company in the world. With seemingly unlimited funding and the only working in-line chlorine generator on the market, there was no doubt the 'GeniChlor' was poised to revolutionize swimming pool maintenance.
The State of Florida was impressed enough with lab results to allow us to test the GeniChlor on a number of Central Florida commercial pools. All we had to do was get Geni to live up to most of the hype.
Problems came hard and fast.
When you're breaking salt down into chlorine and sodium in a real pool, the diode plates can clog up pretty quickly and a clogged plate can't generate. The Geni had a built in cleaning system using Nitric Acid, but was manually activated and many of the machines could not go more than a few days without cleaning. It was an unusually hot Summer and without a constant supply of chlorine, our pools could turn green overnight. With the Health Dept focused on how the Geni performed, we became experts in the 'subtle shock' chlorine treatment; killing the algae without bleaching out the guests.
When you run pool water and salt solution through a generator an unexpected byproduct is Hydrogen gas; surprise, surprise. The Big Surprise came when a clogged filter killed the flow and a spark from an overheated circuit ignited any Hydrogen gas built up in the mixing chamber.... which explained the shards of blue glass and little bits of plastic we'd find strewn around a pumphouse where we'd placed a GeniChlor.
Question: What's all this talk about chlorine? I got a salt system because I can't stand chlorine and the salesman told me this killed germs through magic and commissions.
Answer: Salt systems are chlorine systems. What they do is ionize salt into hypochlorous acid and caustic soda from one of the most common chemical compounds on this planet. Chlorine is chlorine, whether you extract it from a tablet, liquid or rock hard mineral.
A pumphouse is also a far more damp environment than is a lab. Electronics don't like damp. If the exterior case isn't pretty close to waterproof, delicate circuits oxidize and the entire unit goes dead.
Those are the problems of which we were immediately aware. More subtle problems were to follow.
Electronics hate brown-outs. If you live in an area where the electricity fluxuates on a regular basis, you can figure the controller will last three to five years. Certainly, don't count on much more.
(photo top right) You've got to treat salt water like acid, especially around equipment. A spritz leak in the pressure- side male adaptor literally dissolved this motor frame in a few months. Where bolts add stress, whole chunks of the motor bark away like popcorn.
(photo above) Once opened and damage noted, there is no getting this motor back together.
Salt water affects everything it touches. This includes the shaft seal that prevents the pump from bleeding pool water directly into the motor. When you put a salt system on an existing pool, you've got to install a salt resistent shaft seal or it will surely leak.
(photo right) Salt water also dissolves brass heat sink cones. Without a heat sink in which to seat the shaft seal, you'll have to epoxy the next larger size seal to get a waterproof seal on the shaft.
And, if you haven't heard enough bad news, there is compelling evidence that salt water pool splash-out dissolves some deck materials; particularily Tennessee sand stone, Florida sand stone and the original Kool Deck (Trinity White cement & white masonry or yellow contractors sand), whether it was mixed on-site by hand or from bagged goods from CL Industries (Orlando) or Mortex (Tucson). When sealer was applied, the sand stone was seen to dissolve beneath the sealer leaving only a crispy film.
Central Florida is commonly used as a test market for most of the pool products you're familiar with and many you will never see. On the Pool School PRO CD, we diagnose the most interesting dozen or so chlorine generators tested in our market, praising their strengths and exposing their weaknesses. It's interesting to note how these latest machines wrestle with the same problems we faced with the original Geni Chlor.
We need come up with a generator that will reliably separate chlorine from salt and typically do so for a decade or more to make salt machines as conventional a piece of maintenance equipment as the standard pump, motor or filter. Until then, the only revolution has been in the selling of chlorine generators; the marketing of lowered expections. As it is now, we can't offer a product that will last more than a few years. The typical warranty is one year. I have not yet seen the generator that has lasted more than six years, with a three to five year cycle as typical. It's a serious enough problem that most electrolytic cells come with quik-connects to make replacement a simple and routine event at $450 to $650 (US) a pop.
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