Any way to extend life of Pentair IC40 after Check Cell light starts blinking?

[peterl1365]

I've cleaned the cell 3 times over the last few weeks, but the Check Cell light won't stop blinking.

Today, I observed more closely. After powering up the cell, it takes a minute or two to do diagnostics and then the light turns on to a steady green.

At this point, I confirmed that it is producing chlorine by observing a lot of small bubbles at the return jet.

After about 5 minutes, the light starts blinking and the bubbles stop within 5-10 seconds.

So, is this cell basically dead or is there a way I can hack it to wring the last bit of life out of the plates before completely replacing it?

Not complaining too much about this cell since it has lasted 6 seasons, but still kind of annoyed since the onboard diagnostics appear to indicate that I've got 5000-6000 hours of life remaining.

 

[JamesW]

What's the salinity?

 

[peterl1365]

Around 3500-4000. Haven't added any salt for about 2 years or done any significant water changeout.

 

[ajw22]

Around 3500-4000.

That is measured by what method?

 

[peterl1365]

By the onboard sensor (via the EZ touch interface) and with a salt meter at my last pool store test about 3 weeks ago.
I forget the exact number, but I know it was below 4000.
It had been elevated for a while because I added 2-3 bags a couple of years ago before I realized that my flow switch was giving bad salt/temperature readings

 

[JamesW]

If your salinity is at least 3,800 and it's still giving the error, then it's probably time for a new cell.

 

[peterl1365]

Yeah, I've got a new one on the way. Was just wondering if there was a way to hack it for a few more months worth of use.

 

[JamesW]

Raising the salinity can sometimes help if it's close. Depends on how high you're willing to raise the salinity to try to make it work.

 

[peterl1365]

Raising the salinity can sometimes help if it's close. Depends on how high you're willing to raise the salinity to try to make it work.

Thanks for the tip, but I doubt it will help in this case. The salt is already a little bit high so I don't want to go too much higher.
Makes me wonder, though, has this worked for anyone else? I've had low salt readings in the past, and replacing the flow switch took care of that. I'm curious what the root cause of the check cell failure is. How does the cpu in the cell determine that the cell has deteriorated to the point of failure?

Oh well, 6 seasons is not too bad for this cell. That's 3 years longer than any of my previous IC40's have lasted.

 

[JamesW]

The cell measures current. If the amps are too low, the cell decides that it's bad.

 

[peterl1365]

I see. That would explain why upping the conductivity might trick it into working. Also seems like a very finicky measurement, as the difference in conductivity between 3000 and 4000 ppm is probably quite low, not to mention the variations introduced by other TDS.
This probably also explains why so many of the IC40's fail prematurely.

 

[JamesW]

When the cell is operating properly, the dc current is above a specific level.

When the cell begins to fail, it uses less power because it is not making as much chlorine.

Increasing the salinity or water temperature will increase the production of chlorine and use more power and amps.

Sometimes this helps and sometimes it doesn't depending on how far gone the cell is.

I would suggest that the salinity not be increased to more than 4,500 ppm in an attempt to make the cell work.