Is More Better When It Comes To Chlorine Generators?

In Blog by Timothy Petsch

So you are looking for a Chlorine Generator – or “Salt system” – for your larger commercial pool and the local Pool Company tells you that they can get this type of equipment. They recommend installing a number of smaller units (that they get from a large pool equipment and chemical distributor), instead of one larger commercial unit.


The benefits, they say, are an overall less expensive initial cost, the availability of a local service provider, and constant chlorine back up. By having multiple smaller chlorine generators (also known as cells), you’re never left without the ability to produce chlorine should one or two fail and need replacement.


In some ways that is true, but let’s dissect this train of thought and see where we get.


The first claim is a cheaper upfront cost. This may – or may not – be true, but you also must look at the ongoing cost. How often will you replace a cell? What warranty does that cell carry? How much does each replacement cell cost once it is out of warranty? Since multi-cell installations are often comprised of salt systems designed for small volume commercial use (spas, children’s pools, therapy pools, etc.), or even strictly residential use, they often do not have the robust construction needed to stand up to the chlorine demands of a large volume commercial pool. Each cell is being asked to work at, or near, maximum capacity all of the time, which therefore shortens the lifespan of the cell and prompts early failure.


When a cell fails you have two options: order a replacement right away, or rely on the other cells to cover the load for a while. Since the facility must pay shipping costs or service and installation fees on each cell, they often wait for two or more cells to be down before replacement occurs. Spreading the same chlorine demands over fewer chlorine generators forces each remaining cell to work that much harder, which decreases the life span of each, which increases the failure rate. It’s a self-perpetuating cycle. For example, I recently reviewed two bids for an aquatic facility looking into a salt system. The facility required a 20lb production capacity. One bid offered a single cell system that could handle that load. The other bid suggested 18 cells. 18! When the numbers were run for 10 years out, the 18 cell system would have cost the facility more than double that of the single cell unit. This is exactly why it is important to have a good understanding of what ongoing costs will be, before undertaking the installation of a multi-cell system.


There is also a tangible cost element in maintenance time. Each of those small cells will need to be removed from their housing periodically for inspection and cleaning. Even the best “self-cleaning” (polarity reversing) cell must be cleaned from time to time. Without this regular preventative maintenance the cell will build up a layer of calcium, which reduces the chlorine output of the cell and forces the cell to work harder than it has to. When that cell fails, its calcified state may disqualify it for warranty coverage. While one or two properly sized commercial cells may only require a few minutes’ visual inspection and minimal routine maintenance, how much time will five, six, seven or more small cells require from your maintenance staff or pool service technician? How much will their time cost you? Additionally, each cell will have its own power supply. Each power supply will need routine inspection as well, not to mention that more parts translate to more potential points of failure down the line.


Then we come to the benefit of local service. Here are a few more questions you should consider when shopping for a salt system. One, how soon can they get to you if you need help? Many service companies book their weeks up in advance, so if you need on-site service, you may be in for a wait. Have you budgeted for their time on site? An issue with the system may require a diagnostic visit, followed by a repair visit. Will they have the parts you need on hand or will they need to order them? Many local providers sell a number of systems, making it hard for them to keep all necessary stock on hand. Have you budgeted for back up chlorine, should you be left waiting for replacement parts? Also consider that salt systems are often not their specialty and you could be one of their first commercial installations. Are you OK being part of their learning curve?


In conclusion, a small multiple cell unit will not only cost you more (sometimes a lot more) money in the long run, but will add a ton of maintenance time to your pool operators already busy day. Although a larger commercial unit may initially cost more, you end up with a salt system that has been properly sized to your sanitation needs, that needs less time spent on maintenance and replacement, and that comes from a company that specializes in that equipment only. By working with a specialist, your tech support representatives know everything about your system, rather than a little about many, and will have replacement parts on hand should that be necessary.


Which option sounds like the best for you?