SWG dying?

[Slash308]

Relatively new pool owner, existing ~5 yr old plaster 10k gal pool. Think my salt cell(original install) is dying, but want a 2nd opinion/sanity check. Goldline controls, T-15 cell. Inside control panel and circuit board looks brand new. Fuses good, no discoloration/burns. Pulled and cleaned the cell with 5:1 31.5% muriatic, was pretty clean with very minimal scaling, not anything like some of the horror pictures I have seen on here.

I run the pump on high at least 4 hours before any tests.

Using Aquachek salt strips, I get 4850PPM salt. Using Taylor R-1766 chromate test, I get 4600-4800PPM. Control panel says low salt, varying between 2200-2500PPM, occasionally cell switches off because salt reads too low.

Cell: -28.5 Volts, -4.66 Amps this morning
+27.6 Volts, +4.92Amps this evening

PH - 7.8
FC - 1.5
CC - 0.0-0.5
TA - 75-80
CH - 290
CYA - 60
Borate - 40-50
Temp - 78°F

Yes, I know chlorine is a bit low, and CYA is also a bit low. Been slowly working up CYA. Was between 0 and 10 when I bought the house, and 9" of rain in the last week is not helping at all. After these tests, I did add a half bottle of plain old unscented Clorox.

 

[JasonLion]

Welcome to TFP!

That does sound just like a worn out cell. It is worth doing a visual inspection of the cell just to make sure there isn't any calcium scaling, which can produce the same symptoms. Assuming the cell is clean, it is time to get a new one.

 

[Slash308]

Replied too quick. Hah. Was editing the original post to say cell is pretty clean.

Was hoping I was wrong. There goes some beer money.

Thanks for the quick reply!

 

[jblizzle]

Is the new cell going to have problems at your high salt concentration? Not sure if Hayward has a high salt cut out.

 

[Slash308]

I'm not even going to find out. Doing a flush. Water is much cheaper than a salt cell or a controller. I'm shooting to bring it down to 3300-3700. Recommended upper limit as per the manual is 3300. I think it must have a high cutout, since I have found the low cutout.

I don't think 500(15%) over recommended would hurt anything, but at 1500(45%) over and a new cell, I am concerned that the circuit resistance might be dangerously low.

The old cell is still putting out something, so I'm going to run it 100% duty cycle for a couple days to try to pull the FC up while I incrementally drain and fill. Not like it's any loss if I kill the old cell. Ordered a new Hayward T-15.

Is 5 years typical for a T-15 on a 10k gal pool in a southern climate?

 

[JasonLion]

Yes, three to five years is a typical cell life, though there is a fair amount of variation both shorter and longer.