Most pools use liquid chlorine to sanitize the pool water. Some people prefer using salt to sanitize the pool water. Salt water chlorination is a process that uses dissolved salt. There are two parts that make up a salt water system. The chlorine generator uses electrolysis to convert the saltwater to chlorinated water. As such, a saltwater pool is not actually chlorine-free; it simply utilizes added salt and a chlorine generator instead of direct addition of liquid chlorine. The control module reports current salt level and calculates how much salt needs to be added to the pool to maintain proper chlorination.
We bought our salt water system in May of 2013 at The Recreational Warehouse store in Fort Myers. We had a local pool service company install it. We like the saltwater system much better than the old liquid chlorine method. We find the water better for swimming in and the chlorine levels have been easier to maintain than our previous method.
As a REALTOR® out looking at homes, I see a lot of saltwater control modules severely damaged by the sun. The control module is one the most expensive parts of the saltwater system. To protect this part from the sun, I suggest you place a sunscreen over the module. The sunscreen can be as simple as using an old piece of a thick sheet or pillowcase to cover the plastic control module. What I did to make a sunscreen was to first cut a hole on each side of a pillowcase near the top. Next, I attached the sunscreen over the top of the module (between the mounting bracket and the wall) using the mounting screws.
See the images above for our saltwater system, the module looks near new after many years and it gets direct sunlight all afternoon.