Intellichlor not producing chlorine

[MostlyCanuck]

Have been incrementally increasing SWG % output recently and supplementing with liquid chlorine… at first I thought it was just hotter than normal, perhaps stronger UV….
Now there’s zero chlorine in the pool despite SWG having been set at 50% or more for a week and pump running 24/7 as always so the thing is clearly not generating chlorine.
All lights are green and fine, no error message. Cell is clean, no scaling. Pool is clean. CYA is in ideal range and flow is strong. I tested chlorine with 3 different kits to be sure!

Anyone have any clue? I know general notion is that when lights are green the cell works, but obviously that is not the case here..

 

[mknauss]

Do you see hydrogen bubbles out of the returns when the SWCG cell light is green?

 

[MostlyCanuck]

No

 

[mknauss]

I cannot say I have heard of a cell that failed with all normal lights, a cycling CELL light based on the % generation, etc.

Normal would be algae is consuming the FC as fast as it is being made. Your Poolmath logs do not show a low FC.

Let's ask @Jimrahbe for his input.

 

[Jimrahbe]

MC,

At 50% does the "Cell" light come on for 2.5 minutes and then off for 2.5 minute, etc.???

Is the cell light flashing?

How old it the cell?

Normally when the cell is not making chlorine the "Cell" light will flash, or all the lights off, or it will pop the breaker.

Thanks,

Jim R.

 

[MostlyCanuck]

All lights green solid, not flashing.
Cell light cycles on/off every 2 min approx with output set at 50%.
Unit was installed new last summer (assuming PB installed a new one ahah)
Literally everything looks perfect except there’s no chlorine in the pool.
Unit is way oversized for my pool, so at 50% with 24/7 flow should yield a whopping 8ppm I believe so this really blows my mind.
I turned the cell off at the breaker, then back on set it to 100 for a couple hrs and back to 50% and now as the cell cycles I can actually see the oxygen bubbling out of returns. I wonder if the “hard reset” I performed did anything…
I will monitor for a couple days and get back to you here… in the meantime any ideas as to what might be happening are welcome

 

[Jimrahbe]

MC,

Sounds like a plan to me.

One thing, just to make sure... the Cell will only make chlorine if your IntelliCenter is in Auto and the Pool or Spa modes.

Here is an example of a "bad" schedule.. Thinking the SWCG will be on from 8 am until 8 pm, just because the pump is running.

Pool from 8 am until noon - SWCG will be on.
Cleaner from noon until 8 pm - SWCG will be off.

Thanks,

Jim R.

 

[MostlyCanuck]

My schedules are attached. Circuit is always set to Pool other than 1hr each morning for a quick skim - I think they’re fine!

 

[Dirk]

FYI. It's hydrogen bubbles coming out of the returns.

Just to be thorough (as I don't trust pool guys any more either), you could run an "hours usage" check on the cell. From the manual:

IntelliChlor SCG Usage Hours Meter
The IntelliChlor® SCG provides a built-in cell “usage hours” meter that reports how many hours IntelliChlor has been operating. The IntelliChlor SCG is designed to operate for approximately 10,000 hours before replacement is needed or roughly five (5) years of average use.
To access the system status mode:

1. Press and hold the MORE button for three (3) seconds until the lights scroll across the unit.
2. One (1) of the five (5) Sanitizer Output LED indicators (20%, 40%, 60%, 80% and 100%) will be lit,
   indicating the hours of usage. The Output LEDs are as follows: • 2000 hours (20% LED on)
   • 4000 hours (40% LED on)
   • 6000 hours (60% LED on)
   • 8000 hours (80% LED on)
   • 10,000 hours (100% LED on)

Also, you could have a look at the plates to see if there is some unusual amount of calcium build up. That entails removing the unit from your plumbing and peering inside.

Or, since your unit is still under warranty, you could call Pentair and have them send a tech to your home and let them deal with it. If they don't know what it is right away, they'll probably just swap in a new unit.

 

[Jimrahbe]

MC,

Your schedules are fine, I was just making sure that you did not have the problem that I have seen on other systems.

If you are worried about how old the cell is, it has a date of mfg. on the S/N label. On the bottom so just take a pic to read.

Thanks,

Jim R.

 

[MostlyCanuck]

Thx gents - I did the runtime test suggested and actually none of the output LEDs are lit which I assume means fewer than 2000 hrs. Manufactured in 2020 according to label. So at least I know PB didn’t install a used unit!!