Intellichem pH 4.04, ORP NEGATIVE 12 incorrect readings
- Thread starter C.Klages
- Start date
Allen, I agree with simpler is usually better.
But some battles are not worth fighting your hubby about, lol. The UV sterilizer is behind the SWCG to avoid the UV eating up the chlorine that is generated, so that's never been an issue. We have gotten correct chlorine levels on a fairly consistent basis till this problem popped up. I'm thinking, and maybe I'm wrong here, that it 'might' be a cable to the board or a board problem??? Anybody ever have issues with that and get a NEGATIVE ORP number? It's very odd that the readings I'm getting on the display are not matching up with real readings, especially after replacing both probes with brand new probes. Other than this, we're not having problems balancing our pool numbers and our water looks nice and clear here in sunny Florida where it's open year round. We adhere to the general PoolMath suggestions, with the exception of keeping our chlorine around 1.5 (increase it when we're expecting a party, though), and we keep the CYA as low as possible. It's only since replacing probes that this problem has cropped up. The Intellichem is trying to do what its's designed to do--tell the IC40 to make chlorine when the ORP is low. It's just now it's making too much chlorine because it's getting false information somewhere along the line.
James, I've checked, and also double checked that the tech checked when he put them in.
Were the readings accurate when the sensors were replaced?
Did you personally see the readings?
I've checked, and they appear to be. I also asked the tech to double check as he installed them.
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How sure are you on the CYA reading? I’ve read CYA screws up ORP readings. Long shot but something to check if a pool store measured it as they get it wrong very often.
- Jul 21, 2013
- 52,845
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
The UV consumes the chlorine flowing through the pool water. It does not matter if the UV system is before or after the SWG. The chlorine does not stay in the pool with non-chlorine water flowing back through the pump.
ORP is an indirect approximation of chlorine level. The IntelliChem is always getting false information on what the real chlorine level is. Especially once CYA is put in the water.
I must admit that i was off to the side when he did that check-i did see him go to the place in the software that you test the calibration. However, when i looked back again, I don't think it said "FAILED" anywhere on the screen. I suppose we could go out and actually do the "meter test" again to see. Thanks.
Thanks.
Auto Calibration appears to be occuring upon start up, and then gives the false values and goes into 'dosing mode' telling the IC40 to make chlorine. See pictures of screen on startup (after the standard flow delay) below. I do have flow going through the flow sensor (ours happens to be clear so we can actually see the black float go up and down when there's flow or not) Also, it detects flow at the start.
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All you say is correct. However, usually the ORP values are somewhere in the hundred, not NEGATIVE digits, as changing as they always are. We understand how ORP works and its unreliability as to an accurate chlorine reading. The ORP stands for Oxidation Reduction Potential, not chlorine.
We don't rely on the ORP value to solely dose our chlorine. It has (before this weird occurence) given us readings that pretty much stay within the range we preset for it, which allows the IC40 to produce chlorine at a sufficient amount while we are away for several weeks. We know we have to stay on top of it and adjust the chlorine levels based on our Taylor test kit, and that is how we knew the first time (a month or so ago) that there was a problem. Our chlorine levels (via Taylor test kit) had shot up to 10 in a matter of 2 days after the tech replaced the pH probe, and that's when we noticed the ORP had changed from its regular 650 to -12. And then again when he came back yesterday and replaced both probes, it's following the same pattern. Our CYA levels have always been extremely low. Like, we never even cloud over the dot at the bottom of the test tube. The lowest the kit will give us is 30 CYA, but in all reality, it's probably a lot less than that. We don't have a lot of bathers or debris in our screened in pool, so there's not much that the chlorine has to fight and produce CC.
I'm positive the CYA readings are correct. We do our own testing via our Taylor kit, and the 'black dot' never disappears from view. At first, we were skeptical, so we ordered a different bottle of Cyanuric Acid Reagent in case we had expired stuff in our kit, and we got the same results. Took it to a pool store and they got the same results. So, we figure we're still doing the testing correctly, and our CYA is no higher than 30, and it could possibly be lower than that. So we definitely do not have high CYA which would definitely screw up the ORP readings, but still not by pushing them into negative numbers. Thanks for the idea, though.
Do you still need pictures, or are the ones in the thread what you wanted? If you need others, let me know which parts of the system you want pictures of.
Here's everything, lol. You can zoom in and read the labels we printed to track what everything is and the directional flow. MDV AND Ozone are mounted on the wall. Insertion points are marked with printed labels on the pipes. I didn't take a picture of the Riverflow pump that we use to paddleboard against, but you can see it on the pool upper deck photo, behind the orchids. It just pumps directly from the pool back to the pool with no interaction to the rest of the system. It's great for mixing in the pool chemicals like salt, though, lol. Let me know if there's something You want a better photo of.
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Does ozone inject before the sensor intake line?
What does the builder say?
What does Pentair say?
What does the builder say?
What does Pentair say?
What are the lines with the red dots?
Are they the sensor lines?
If yes, it does not follow the diagram.
Which one is intake and which one is return?
Are they the sensor lines?
If yes, it does not follow the diagram.
Which one is intake and which one is return?
Ozone insertion point is after the salt cell. You can see a close up in picture 3348. The insertion point your red dot is on before the salt cell is actually the Acid Insertion Point. And your other red dot is the return from the Intellichem back to the system (the low pressure side). The sampling port for the Intellichem is just in front of the UV on the high pressure side, before the water goes into the heatpump. Pentair says the plumbing is correct, and so does the builder.
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