I will be the first on this category. This was some of the information that I was looking for when first looking for a pool. So, here are my questions:
1. What is an SWCG (Saltwater Chlorine Generator)?
This is a device that will generate chlorine automatically using chloride (from salt) that is added to your pool. Because chlorine eventually breaks down or gets used up and turns back into chloride, you only need to add the salt once initially. The device is plugged into a power source and uses electricity to generate the chlorine in the pool water. Usually, this device is placed in-line in your plumbing as the last item before water gets put back into your pool (i.e. it comes after the pump, filter, solar panels, heater, etc.).
2. How does it work?
It works by a process called electrolysis. This just means that electricity is used to create chemical reactions that would not occur naturally by themselves. The SWCG device contains two sets of metal plates, one of which is positively charged and the other is negatively charged (at voltages ranging from around 6 to 27 volts depending on manufacturer). At the positive plate, chlorine gas is produced, but it immediately dissolves in water to produce the disinfecting form of chlorine (hypochlorous acid) plus hydrochloric acid. At the negative plate, hydrogen gas is produced along with hydroxyl ion. The net result is that chloride ions (from salt) in the water are converted to the disinfecting form of chlorine.
The chlorine produced by an SWCG is identical to the chlorine from other sources, including bleach. However, it only consumes electricity to do this and does not introduce other chemicals into the pool.
3. Once I have chosen the process of SWCG, what are the most typical settings to use throughout the year?
I don't know. Someone else can answer this, assuming you mean setting like how long is it typically on or what power setting is used.
4. What are some of the pros and cons to my selection?
Some of the pros don't have to do with the SWCG per se, but rather with having more salt in the pool (typically around 3000 parts-per-million or ppm -- for comparison, the ocean is around 35,000 ppm). The salt in the pool feels silkier and is less harsh on skin and the eyes (less stinging or drying out). The biggest pro for the SWCG itself is convenience. You don't have to buy chlorine and add it to your pool. It is also more likely for your pool to remain sanitary and to not get algae because the SWCG won't "forget" to add chlorine, plus it does some super-chlorination in the SWCG itself.
Some of the cons include a greater tendency for the pH to rise in the pool, requiring you to add acid relatively frequently. There are methods to reduce this problem, but it is not eliminated and is caused primarily by the aeration of pool water from those hydrogen gas bubbles I mentioned that are produced during the electrolysis. The other main con is the initial cost (usually around $1000) and the cost to replace the cell (usually around $300) which may be needed every 3-5 years. The cost of generating the chlorine is quite a bit less than chlorine from other sources.
Other cons are controversial and not seen in all pools and are mostly due to the increased salt in the pool (not the SWCG itself) and include possibly greater corrosion of soft limestone or other susceptible surfaces (if not sealed or hosed off or resistant to salt water). There may be a greater risk of metal corrosion, especially for salt water dripped onto non-stainless steel in pool chairs, etc. The salt water is more conductive to electricity so may increase the risk of shock (mostly tingling) if the pool is not properly bonded.
For the most part, people who have SWG pools love them and find the convenience very compelling.
Wow...our pb just gave us a quote of $2300, which is a huge con for us. Is that price way out of line? Any opinions will be appreciated.
