How did you verify that the cells were not producing chlorine?
The cells were probably fine. With the first two units I had to keep raising the output on the keypad to maintain FC level at 4 -5 ppm, and eventually the FC dropped off completely (not caused by higher demand). The 3rd unit just went totally dead.
Are you replacing just the cell or the cell and power supply?
So you replaced what? I haven't replaced anything yet - I'm using liquid chlorine at present.
If the fuse was bad, you don't need a new cell or entire power supply. The fuse receptacle in the power unit was melted down, so the power unit is not usable.
Are you doing everything yourself or do you have service people who are telling you that you need new equipment? Long story short: I live on a smallish island in the Caribbean - competent equipment suppliers and "pool guys" are hard to find. So with the help of TFP I have been doing everything myself (electric installation excepted).
Seems like the system should have been under warranty for at least some of the problems. I bought my 1st SWG from a supplier who offered a maximum 6 month warranty which unfortunately is standard practice here. I soon realised that the supplier did not know much about the equipment he was selling. The next 2 units I bought from Amazon. USA warranties are not practical in the south Caribbean .......... to claim on the warranty I would have to ship the faulty unit back to the USA.
Most likely the problem is not with the equipment.
Most likely, there is an onsite problem like chemistry or electrical problems or the local service people are not doing a professional job (incompetent or dishonest). Prior to this thread I had not thought to check the electricals, but I will definitely investigate.
What does Pentair have to say? I have not contacted Pentair. I had seen some reviews indicating that Pentair SWG's had been failing in under 2 years, so I assumed their SWG's were just a bad product. But the responses received on this thread indicate otherwise, and I am grateful for the different perspective. I will get the electricals checked and update you guys. Thanks again.