Salt Chlorinators – Frequently Asked Questions
- Do the Salt Chlorinator units produce the amount of chlorine needed to satisfy the chlorine demand in the pool or do they just produce chlorine at a set rate determined by the chlorinator?
- Does the unit warn when salt levels are too low?
- Approximately how much salt will I need per month?
- What is the cost of salt?
- How long do the electrodes (cell) last?
- What does the replacement cost?
- Are there any other serviceable items?
Salt chlorinators for swimming pools were designed as an alternative to physically dosing a pool with granular chlorine such as HTH or Ultraswim.
There is a fair amount of uncertainty around how salt chlorinators work, and below are some of the frequently asked questions we get as swimming pool professionals.
Do the Salt Chlorinator units produce the amount of chlorine needed to satisfy the chlorine demand in the pool or do they just produce chlorine at a set rate determined by the chlorinator?
Chlorine demand in a swimming pool can vary depending on many circumstances.
- Bather load
- Pump run-time
- Water balance
- Stabilizer level
- Condition of the filter sand
- Amount of foliage in the pool.
While there’s a way to determine what the ORP (Oxidation-Reduction Potential) is in pool water, this doesn’t indicate the free available chlorine (FAC) in pool water. These test probes usually require manual manipulation to give us some idea as to whether there is enough oxidation in the pool. The pH of the water also plays a huge role in sanitising a pool.
In South Africa, these technologies are becoming more and more available in the market, but to a large degree, physically testing the chlorine residual and pH with a standard test kit or test strips is the easiest way of staying on top of your swimming pool water condition.
A Salt Chlorinator is usually categorised by what it’s chlorine gas output can do. (For example 25 grams per hour, or 40 grams per hour, etc.) Therefore, the longer the chlorinator runs (and it can only run when the pump is running and the flow through the cell is good, the more chlorine will be introduced to the pool water.
2. Does the Salt Chlorinator warn when salt levels are too low?
Yes. Most Salt Chlorinators have a sensor that indicates when salt needs to be added to the pool.
3. Approximately how much salt will I need per month?
The biggest cause of decreasing salt levels in pool water is dilution. So after backwashing and when the pool needs to be topped up, the fresh tap water used has no salt in it. Rainwater also has no salt in it, so when this water is mixed with pool water, the salt level decreases.
On average, in Durban, An 8 x 4 pool ( which has approximately 50, 000l of water) would require 3-6 25KG bags of salt every three to six months. This is an average and will vary from climate to climate and from pool to pool.
If a saltwater swimming pool has a water leak, then the frequent topping up of the pool water will dilute the salt quicker, and more salt will be required than usual to maintain the salt level.
4. What is the cost of salt?
A 25KG bag of salt usually costs between R100 and R150 depending on where you buy it from.
5. How long do the electrodes (cell) last?
The life span of the cell depends largely on how you look after the pool water balance and the salt level. Running the unit with too little salt in the water causes the cell to perish sooner.
One can expect to get 2-3 years out of a cell, maybe longer. Most units carry a 1-year warranty, and usually, only the cell needs to be replaced, not the power supply.
6. What does the replacement cost?
This depends on what make of Salt Chlorinator you have. The cheaper cells range from R2800 to replace and the better quality ones can cost around R7000 to replace. The better quality salt chlorinators usually last longer and are lower maintenance than the cheaper ones.
7. Are there any other serviceable items on a salt chlorinator?
The entry-level salt chlorinators may need a few parts serviced such as the power switch, the electrode gauge and the fuse, etc. The better quality salt chlorinators usually only need the cell replaced once the cell life has ended.