Just to follow up on this in case someone with a similar problem searches the forum for help.... My old cell was clogging up quickly between cleanings. I know I have high TA, but I've always had high TA, and the speed of build-up was increasing over time. Moreover, even with a spotless salt cell and known good levels of salt in the pool, I could not get my average reading above 2400 for any length of time (instants were always around 2100 or 2200, with voltage levels at 25.2 or higher, though the amp readings were usually fine). Within a couple days of a recent cleaning, my average would drop to 2100 and the system would shut down. I could trick the system into starting off with a very high average (the click off, click on, wait for sound of generation starting, cycle display to instant read, and immediately flip up to super chlorinate and back to on to lock in something in the high 3000s) but that was a only temporary fix. I knew my cell was done. Whether it was due to normal wear of the plate's surface elements, bad manufacturing, or from me giving the cell too many acid baths I'll never know. So I searched the net and found two options. One was a CompuPool replacement cell for $350 (shipping and taxes included) from Pool Supply Unlimited with a 3 year warranty. The other was a Hayward T-Cell-15 OEM model for about $440 (S&T included) from Pool Supply 4 Less with a 3 year warranty as well. The $90 difference was very attractive, but everything I could find about CompuPool suggested that warranty returns were a nightmare, even if they accepted the fact that the unit failed (stories of months waiting for the replacement are common). I figured that it was almost certain that I'd need to take the unit back to the manufacturer in the next three years, and if I did so, Hayward would probably be the better option. I live in Southern California and there are official Hayward service centers scattered around this part of the state, which would make things easier even though I bought the unit on-line from a discount supplier. I swapped in the new T-Cell-15 and as I suspected, the pool readings were just fine. I now have averages of 3200 to 3400, instant reads in about the same range, and voltage\amp values within recommended numbers. One of the things that ticks me off is that I repeatedly went to Leslie's in the last two months to have them test the old cell, and in every instance they said it was just fine. When I'd plug it back in upon returning home, I'd be back down to 2300 average in an hour, just hovering over the shutdown level. They, and Hayward's customer service department, kept telling me that it wasn't my cell, it was my controller, and that I should buy a complete new system (of course!), but the satisfactory readings from the replacement cell suggest that they may have interests other than my best ones in mind when developing their recommendations. Good luck to you if you are reading this! ...

Was there any insect evidence like a cocoon? They can short out a component without any outwardly visual signs. Did you check the leads in and out of the transformer? If these areas show no problems, then the control board has died and will need replacing. Scott

You'll have to break down and buy a new sensor, that's likely the issue. If your cell is over 4 or 5 years old, it may make sense to buy the cell and sensor combo, as they have discontinued the 1400 older design. Our old cell just crapped out after 4 years. 4-5 is the life cycle. The new design has to be replumbed, but if you are handy, it's easy PVC plumbing....About $800 for the replacement cell /sensor on the internet... Yes, shock the pool, and get some algae control in there. We use a bag or 2 of shock every once in a while after the pool gets a heavy kid use. You are going to need to shock the water to get the chlorine level up anyway before you re-start the salt system to give it a jump start.

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