Pentair SWG / IntelliChem / Intellichlor Questions

[PoolDunce]

Our system is controlled by the pentair intellichem / intellichlor which keeps our pH (Muriatic acid tank) and ORP mostly within normal range
On water testing, our alkalinity is very low (25) and cyanuric acid (CNA) is essentially undetectable. Free chlorine is 2-3.
The intellichem says that CNA should be less than 30.
Our pool guy however says that the CNA should be between 30 and 50 and that pentair can't put that for "legal" reasons.
Questions
1) Do we need to add CNA?
2) if the pH is within normal range, do we need to increase alkalinity?

 

[Newdude]

Hey PD and Welcome !!

The intellichem says that CNA should be less than 30.

They updated their SWGs to 30 to 50, so it's only a matter of time before it's across the board, if it isn't already. How old is the unit ?

On water testing, our alkalinity is very low (25) and cyanuric acid (CNA) is essentially undetectable. Free chlorine is 2-3.

How are you testing ?

 

[PoolDunce]

Hey PD and Welcome !!

They updated their SWGs to 30 to 50, so it's only a matter of time before it's across the board, if it isn't already. How old is the unit ?


How are you testing ?

We built a pool last summer so the unit is about 8 months old. I am testing with a standard Taylor nine-way test kit

 

[Newdude]

. I am testing with a standard Taylor nine-way test kit

Ok that's a good start. You need to add a K1515 kit to properly test FC. The comparator block test is more for testing the presence of chlorone and isn't very accurate, plus it only goes to 5. The up to 10 part is for Bromine. What appears as 5 to 10 is really 5 FC / 10 BR and you are testing one or the other.

Your TA needs to be brought to range, but 25 isn't a number from the Taylor kit, so test them all with the kit and post up the results.

A CYA of 60 should be fine for Chicago, but 70 will protect the FC you generate a little better.

 

[Turbo1Ton]

@PoolDunce - You should update the title of the thread to say IntelliChem, instead of just IC. There are several users on here who use the IntelliChem, but not many, and that may help them find your thread.

The way I understand it is with the IntelliChem, a higher CYA concentration messes up the ORP readings. If you raise your CYA above the levels the IntelliChem recommends, it will likely cause problems with the readings and the ORP will no longer control the SWCG the way it 'should'. You can read more about it, and there are instructions for disassociating the SWCG from the IntelliChem here... Pentair IntelliChem - Further Reading

This is about all I know about the IntelliChem. A couple of our chemistry guru's may be able to explain the effect of the CYA on the ORP readings. You may also be able to do a search to find more information on that, as I know it has been discussed before.

--Jeff

 

[Newdude]

You should update the title of the thread to say IntelliChem, instead of just IC. There are several users on here who use the IntelliChem, but not many, and that may help them find your thread

It'll also help me. I read the Intillichem/ORP part but had only IC on my mind from the title. Nice save Jeff.

Pentair IntelliChem - Further Reading

www.troublefreepool.com

 

[PoolDunce]

Update
The pool maintenance from our pool builder was here Friday (About 30 hours ago). I wasn't here but he evidently added a load of bicarb. I know this because now the water is cloudy. It only clears when the bicarb settles to the floor. Total alkalinity is now 150 (Taylor 9 way kit)

Free chlorine is off the charts (again Taylor 9 way kit) but according to @Newdude this may not be accurate. It did bring up another question however. If the pool output on the Intellichlor is set to 40% on the Pentair app, shouldn't the lights on the unit be at 40%? The "pool guy" says to ignore the lights on the unit because the Intellichem is controlling everything. This does not seem correct to me but that is why I am PoolDunce

 

[Newdude]

Free chlorine is off the charts

Was it yellow, orange ? Brown ?

You need the FAS/DPD chlorine test to get an actual # for the level. Buy here

 

[PoolDunce]

I would say deep magenta. Darker than the level at the top which reads 5

 

[Newdude]

I would say deep magenta. Darker than the level at the top which reads 5

Magenta is the PH side when it's messed up from the high FC. Mine becomes readable again with 3 or 4 drops instead of 5.

The FC / yellow side becomes orange and then brown the higher the FC gets.

 

[PoolDunce]

Magenta is the PH side when it's messed up from the high FC. Mine becomes readable again with 3 or 4 drops instead of 5.

The FC / yellow side becomes orange and then brown the higher the FC gets.

 

[Newdude]

Ok. I haven't seen that comparator block yet. I did not know a pink one existed, or I forgot it existed.

But HEY. I made you feel better about being a dunce. So there is that.

What is the same about any of the OTO style FC tests is that they simply can't test over 5, and are sketchy at best below 5. So its really only good to test for the presence of chlorine. In this case, the # is less important because you most likely are plenty above minimum FC until the next test.

If you'd like to know the actual FC, you need the fas/dpd kit in post 8.