Pentair IC40 Low Salt Readings

[Turbo1Ton]

I've been having issues with my IC40 reading low salt levels (<2600) and therefore, not producing chlorine, according to the manual. I pulled the salt cell out and inspected it several weeks ago because of low chlorine production. Plates were clean, but I went ahead and mixed up the recommended acid solution to see what might happen. No bubbling when I put the solution in the cell. So I dumped it immediately and rinsed it and reinstalled. All was ok for about a week. Salt levels were closer to normal and it was producing chlorine again. Now I'm back to having issues with it.

I suppose my question is, are the salinity sensors able to be cleaned, or do they get cleaned with the normal acid rinse? Has anyone else had issues like this? I know the manual states +/- 500ppm accuracy, but mine is more like 1000ppm off. I was at 3400ppm on my last salt test, last weekend. I added a bag last night in order to bring the value closer to the 'ideal' of 3600ppm (a 40lb bag estimated me at 3770ppm). So low salt is definitely not the issue. Clearly something going on with the cell.

Thanks,

--Jeff

 

[Jimrahbe]

Jeff,

This is a pretty well know problem with the IntelliChlor cells.. There is a temperature compensating thermistor inside the flow switch assembly.. When the thermistor goes bad, the cell almost always reads low salt.. If the unit is under warranty, have Pentair fix it. If out of warranty, it is a pretty easy DIY fix.

Thanks,

Jim R.

 

[Turbo1Ton]

Thanks Jim. I've read plenty of the threads on the IC40 but apparently didn't catch that faulty thermistor might be the issue. Definitely should be under warranty; pool was just finished in January. I'll give Pentair a call and see what they say.

--Jeff

 

[Jimrahbe]

Jeff,

Make sure you tell them what the actual salt level is vs. the salt level reported by the cell.. If it is more than +/- 500 ppm, then they need to fix it...

Thanks,

Jim R.

 

[mknauss]

I suspect they will want an independent salt level test result. So be prepared to take a sample to a pool store.

 

[Turbo1Ton]

Ugh... the thought of going there pains me.

 

[Mep32jep]

What is you water temp? Here is what happened to me. Unit showed low salt and therefore shut down chlorinator. Therefore added salt and the chlorinator started again. Went to.Pool Store.to get quick stat readings and salt level was off the charts. Drained some.water and filled up again. Chlorinator stopped working and showed low salt. Went back for another reading and the salt level was still within range. Called Pemtair and was told that the IC40 unit is set for optimal operating at 77 degrees. For each degree below that, the unit reads 100 ppm less salt. I told him I thought he was crazy. He told me.tonget.my.salt level within suggested levels and once the water temp.rose if it didn't work her would send a replacement unit. Well,.this past week our water temp increased and the unit has been working with no problems. I just stocked up on some liquid chlorine to use when the temp was low. Hope this helps.

 

[mknauss]

For each degree below that, the unit reads 100 ppm less salt. I told him I thought he was crazy.

I have a very hard time with that -- my salt level is reported in my ET as 3300ppm in summer (90F water) and 3100 in Winter (55F).

No way it varies that much.

 

[Turbo1Ton]

It is clearly an issue with the unit, as it has registered 3200 before. That was back in March when we were still getting lows where the water temp would get below the 52 degree shut off. When the water temps would come up, say when I was running the spa and the system did the 12 hour check, it would read normal, ~ 3000ppm or so.

Current water temp of 85 degrees today, and it still only reads 2750. Actual tested yesterday was 3400ppm. And that 77 degree limit is bunk. The manual states it should work down to 52 degrees. If you were supposed to reduce the reading by 100ppm per degree, below 77, then the operating temp could only be 67 degrees, because that is where your salt reading would drop below the 2600ppm level required for the unit to function.

--Jeff