Pool Pilot Digital 220 unit - Warning Low Amps - Cell? and Bad Temp Sense

[pacsman]

I have had this unit for 5 years and this is the second SC-48 cell for the unit. The first cell was bad (not getting an chlorine) after the first season and was replaced by the local dealer where I purchased the system. This latest issue started at the end of last season just before I closed the pool for the winter.

The display is reading 28V, 1.4 A (was 28V, 1.7 A last week) and the unit is not producing chlorine, test results below.
I have checked the three fuses, removed them and tested for continuity with a multimeter, all three good.
I have checked all pins in both cables from end to end for continuity and each is good.
Visual inspection of all internal components didn't reveal any signs of burnt wires, popped capacitors, or burnt board components. All connectors reseated. Both fans operating and I can hear the unit click on and off when put in BOOST mode, just as it always has

20'x40', 3' to 8' in ground grecian shaped pool, 28,000 gal, 4 returns, main drain and skimmer, sand filter (new this year - replaced DE filter)
Cell = SC-48
Software Ver 4.2
Power Level = 3 (I just bumped this up last week to see if it made a difference, having been running at power level 2 last three years without issue)
Salt 3400 (pool store tested at 3300)
Actual water temp is at 84 degrees but unit is reporting 75 (again, Bad Temp Sense is one of my issues)
Calcium Hardness = 200
Cyanuric Acid = 0
Total Alkalinity = 100
pH = 7.6
Copper = 0
Iron = 0
Phosphates = 0

I had just cleaned the cell prior to the start of this season, have never had an issue with scale or build-up but did the recommended cleaning anyway. Also cleaned the temp sensor at the same time as my local pool store said that the temp sensor didn't "appear" to be bad. They normaly see signs of the two temperature pickup points being burnt on a bad sensor and they said mine looked fine, recommended cleaning it and trying it again, no change though.

Any thoughts? I don't want to spring for a new cell if there is something wrong with a board or another issue.

[PoolDoc]

. . . membership upgraded.

If you'll look at the bottom of the page, there are a number of threads reporting similar problems. If none are relevant, post again, and I'll ask PoolSean to take a look.

[pacsman]

Thanks for the info. Looks like thread 23752, the first one in the list is my exact problem. Didn't clean the ends of the fuses so will try that and hope that I get the same results.

Thanks for your time in creating and managing this site, very helpful.

[pacsman]

Well, that didn't solve my iussue, no joy here. Cleaned all three of the fuses and still getting the same readings. Also checked the other connections and no corrosion on any of them.

[PoolDoc]

Let me make sure I understand:

1. The cell has been in service for 4 years.

2. The only fault is lack of chlorine production.

3. You have occasional, or regularly, used the BOOST mode.

Is that all correct?

If so, is there reason you aren't thinking that the cell is simply at the end of its life? Are you aware that SWCG cell life is pretty much a straight forward function of "ON" time? And that BOOST mode results in significantly reduced cell life?

[pacsman]

Yes, all is correct. Last year due to the conditions in our area we did use boost more frequetly than in the prior years. I am aware that the life of the cell is limited but wasn't sure how many years I should expect to get from normal use. Having looked around on the internet for others with the same issue, and finding all sorts of reason that the unit may not be functioning, I didn't want to just order up a cell without exploring/investigating all the possibilities.

I also have a church friend whose neighbor uses the same system and was getting similar (not sure if it was exact) messages and it turned out he had three bad diodes on a control board. Once he had the board repaired all was well. Again, I dont know if he had any Voltage or Amperage reading, just that he had the same warning message.

It does appear that my issue may just simply be the cell is at end of life and I need a new one. Just trying to cover all the bases.

So your recommendation would be to purchase a replacement cell? Appreciate your time and feedback.

[PoolDoc]

.
1. Purchase the largest cell that will fit with your system -- a 10,000 hour unit will last 2x as long (in years) if it's used 1/2 as much.

2. Never, ever use BOOST. Use a gallon or two of bleach, instead.

3. Only use your SWCG for NORMAL pool operation -- not for start-up, not for algae, etc. If something's wrong, understand it and fix it manually.

AutoPilot is by no means the worst, but like most 'new and improved' or 'digital' pool equipment, it is often oversold as a complete solution, when in reality it is just a tool with limitations like every other tool. Quite a few people here think the AutoPilot is the best SWCG, but it's still just an SWCG, with all the limitation inherent in the technology.

What SWCG's do well is consistently chlorinate pools that are experiencing normal loads. What they don't do so well, is everything else.

[rcenturion]

my Autopilot cells have lasted around 4-5 years. I use the SC-36

[pacsman]

Thanks for that info. From what I am reading it appears I have been using my system incorrectly and will be making some changes based on above feedback.

[Poolsean]

Sorry to jump in so late, but the information provided in the Original post indicates a warn out cell. Normally the display will show either CHECK/CLEAN CELL or LOW AMPS/CELL?
However, the high volts and lower amps is indicative of a depleted cell, low salt (and the displayed salt needs to be calibrated), or operation during cold water conditions with low salt levels. I would recommended having your water tested to verify the salinity first.
If you remove the cell, inspect for any scale formation on the blades. While you have it out, do the outer blades appear to be worn down along the leading edge of the blades? This is a sign of cell depletion.