Intellichem - and yup orp issue

[Kingston331gt]

So -
I have the Intillichem hooked up. Brand new unit and probes. PH management functionality is perfect. ORP is showing 520ish with perfectly balanced (ideal -.08 LSI).

My numbers
FC =2.8
CC = 0
PH=7.29
CH =320
Alk=110
CYA=18
NaCL=3800


I have read a bunch of posts just saying to use timed dosage as this is typically caused by ORP supression- and I can do that as I know how long to run the IC40 at 100% to get the chlorine generated my pool needs on the 12 hour run schedule. However, that is not why I invested in this and given the plumbing and routing, I do not see how it could be picking up the hydrogen. I invested in this to be fully automated so I would like to get it to work as intended.

• The flow cell input is very far up stream from the IC40; about 6 feet of bends, elbows, a check valve and the heater are between the flow cell input and the IC40. This is plumbed exactly how the manual indicates (down to the check valve).
• I have 7 pool returns around the perimeter and have had the skimmers off to only pull main drain water in to ensure fully mixed water is entering the system.
• I have shielded the flow cell from direct sun
• I have an auto cover that has the pool covered 23 hours a day
• My VS pump runs at 1610 rpm for 12 hours and flows just slightly over enough to keep the flow lights triggering on the IC40 and IChem
• The probe is a gold type and is clean and brand new

• What else has worked for other Ichem users to get them to function as intended? (maybe a moderator could create a forum just for Ichem owners)
• is there a test solution to verify accuracy to in the 700mv range?

Thanks,
Tim

 

[tim5055]

Welcome to the TFP pool! :splash:

My first question would be, what are you using to test your water. Seeing that you are a gadget person I'm gonna guess a ColorQ.

You say -

I invested in this to be fully automated so I would like to get it to work as intended

From the number of folks who report issues with these systems I'm going to opine (no basis other than anecdotal reports) that theses systems are as folks may say, not ready for prime time.....

On another note, you may want to uncover the pool a few hours a day in the sun to make sure you get sufficient UV to burn off any CC that may develope.

 

[Kingston331gt]

Taylor dpd and associated reagents kit(s) are my testing tools.

 

[Kingston331gt]

Still working through this and about to give up and toss this $1200 thing out . I have had to shock my pool twice now in the last month due to cloudy water which is very, very rare for me. My FC is between 1 and 3 consistently with CYA @15~18 (all other chems in range) and CC is zero. The water IS oxidizing as evidence by the white oxidized residue on the bottom, but water still getting cloudy after a week or so. Pentair tech told me to take my water to a pool store for a test.


My Findings:
Cover closed, ORP goes to 750+ system turns SWCG off.
Cover open, ORP drops to below 600 and system turns SWCG to 100%.

This is repeatable with or without sun and take about 30 minutes to drop and raise.

Since the Intilichem only turns the SWCG on and off, so it runs at 100% or nothing. When I was controlling the SWCG manually though the interface - I was keeping it between 15 and 25% for the 12 hours daily cycle. I did some back of the napkin math, and using the production rate of 20% for 12 hours, I need to run my SWCG for just under two hours at 100% (assuming its a linear functions) based on amount of chlorine generated, to use the "by time" dosage and not "set point" method. Neither dosing method is working for me.

So, my hypothesis on cloudy water is this....
SWCG pools perform "self shock" maintenance by creating the superchlorintated environment in the cell as it's working, my pool water turna over a dozen times in the 12 hours it's running and was always clear and sanitized. Because the Intilichem only runs at 100%, it runs for a few hours to get ORP up, but does not have the to chance to "self shock" the entire pool volume, just what flows though it in the few hours until the cell turns off.

My hypothesis on why ORP readings are jacked is this..
The auto cover keeps all the SWCG byproduct gasses contained, which throws off readings and makes



Are these valid hypotheses?


Has ANYBODY, and I mean ANYBODY else with a SWCG and Auto cover actually gotten this thing to work as intended ?


Thanks,
Tim

 

[tim5055]

Taylor dpd and associated reagents kit(s) are my testing tools.

A Taylor kit will not give these results:

PH=7.29

CYA=18

Still working through this and about to give up and toss this $1200 thing out . I have had to shock my pool twice now in the last month due to cloudy water which is very, very rare for me. My FC is between 1 and 3 consistently with CYA @15~18 (all other chems in range) and CC is zero. The water IS oxidizing as evidence by the white oxidized residue on the bottom, but water still getting cloudy after a week or so. Pentair tech told me to take my water to a pool store for a test.


My Findings:
Cover closed, ORP goes to 750+ system turns SWCG off.
Cover open, ORP drops to below 600 and system turns SWCG to 100%.

This is repeatable with or without sun and take about 30 minutes to drop and raise.

Since the Intilichem only turns the SWCG on and off, so it runs at 100% or nothing. When I was controlling the SWCG manually though the interface - I was keeping it between 15 and 25% for the 12 hours daily cycle. I did some back of the napkin math, and using the production rate of 20% for 12 hours, I need to run my SWCG for just under two hours at 100% (assuming its a linear functions) based on amount of chlorine generated, to use the "by time" dosage and not "set point" method. Neither dosing method is working for me.

So, my hypothesis on cloudy water is this....
SWCG pools perform "self shock" maintenance by creating the superchlorintated environment in the cell as it's working, my pool water turna over a dozen times in the 12 hours it's running and was always clear and sanitized. Because the Intilichem only runs at 100%, it runs for a few hours to get ORP up, but does not have the to chance to "self shock" the entire pool volume, just what flows though it in the few hours until the cell turns off.

My hypothesis on why ORP readings are jacked is this..
The auto cover keeps all the SWCG byproduct gasses contained, which throws off readings and makes



Are these valid hypotheses?


Has ANYBODY, and I mean ANYBODY else with a SWCG and Auto cover actually gotten this thing to work as intended ?


Thanks,
Tim

Assuming the CYA of 30ish is correct (from your first post), then keeping the FC in the 1-3 rage is not sufficient to keep algae away.

Now in your second post you say CYA is 15~18, which again is not a result you can obtain with one of the kits we recommend.

I don't think your thoughts of "SWCG pools perform "self shock" maintenance by creating the superchlorintated environment in the cell" are correect either. Even if we calculate that your pump has performed one full turn of pool water, that does not mean that every drop of water in the pool has passed through the filter. Only the exact volume of the pool water has passed thru the cell. Depending on how the circulation is in the pool, some water may never pass through the cell.

I think you have identified the main issue, being the cover. Your statement

Cover closed, ORP goes to 750+ system turns SWCG off.
Cover open, ORP drops to below 600 and system turns SWCG to 100%.

Why the cover closing causes the ORP to jump is baffling to me, but is shows why your FC drops - the SWCG is turned off.

 

[Kingston331gt]

Thanks for your input.

The PH of 7.29 is from the probe at the time I looked at it and the results of the probe have been very, very contestant with the test kit taken across the better part of a month. Between 7.2 and 7.4 has been my range so I have a very high degree in confidence that PH is working 100% properly in both management and measurement.

CYA - Since the original post, I dropped my CYA down to just under 20. And as inaccurate as the disappearing dot test is, it gets you in the range. In fact, I bought the lower scale CYA site tube from here so I could get it about 20 instead of 30.

So - for the sake of this - let's assume the testing methodology and results are sufficient as they have been repeated a plethora of times using different reagent sources and date codes.

Even at a very conservative 60 GPM flow rate of my pump, that is more 40K gallons funneling through the filter and chlorinate in a 12 hour program - which is part of the self shocking hypothesis. I have not changed the duration or speed of the pump and have 7 pool returns, two skimmers and two main drains. It safe to speculate that all of the pool water is going though the SWCG at least once a day.


The cover has no effect on FC test results only ORP readings. I am looking for Intiellichem experience and success, not just typical chemistry advice. Do you have one by chance?

Tim

 

[Jimrahbe]

I am looking for Intiellichem experience and success, not just typical chemistry advice. Do you have one by chance?

Tim

Tim,

Just pulling a number out of the air, my guess would be that 99.9% of our members do NOT have an IntelliChem... I do see several posts by people that have tried to run their pools with an IntelliChem, but after a period of frustration have given up on using it as a fully automated way to maintain their pools.

Let's see if we can get one of the .1% that do have an operating IntelliChem to chime in.

Thanks,

Jim R.

 

[Kingston331gt]

I think we should have a sub forum for these users seeing as how small of a subset and niche product it is and the unique set of problems is has.

 

[JoyfulNoise]

I would say your CYA is way too low. The cover experiment reveals that. When you open the cover, the ORP voltage drops because the chlorine is destroyed by UV light. When you have less than 30ppm CYA, the half life of chlorine is only a few hours (2-3 at most) and so you are losing a lot of chlorine in a short time, so much so that the SWG can’t keep up. This causes the ORP to drop.

As for “superchlorinating” the water in the cell, that’s not correct. Your SWG produces only small increases in FC. An IC-40 operating at 100% output in a 20k gallon pool only adds about 0.35ppm per hour to the pool. The flow rate of water through the cell is quite high with a minimum flow rate of 15GPM needed to activate the cell. If you assume a flow rate of 25GPM through the cell (which is still quite low), then the SWG would add roughly 0.023 ppm per gallon of water flowing through the cell. That’s hardly “superchlorinating” the water.

I’m venturing guess here but your CYA is too low. The problem with ORP is that CYA drops the ORP signal a lot (even with high end gold coated probes) and so increasing CYA decreases the signal-to-noise ratio making the probe less efficient. You’ll need to experiment with your CYA levels, raising them slowly over time, to see at what point you can get a stable working system.

 

[santacruzpool]

No Itellichem here, but I have a cover that is on the pool most of the time. I did some experiments with lowering CYA over the last year plus - I found that as soon as my CYA drops below 30 I start to see higher chlorine loss even when the cover is closed - I found I would need to up the SWG% and/or run time to keep my CL at 4-5ppm with the low CYA. However, as soon as I bump the CYA back up to 30, or even 40 where I am sitting right now, my Chlorine levels seem to hold a lot better and I can run at a lower % on the SWG.

I have a nice feature built into the Jandy automation that allows the SWG to be automatically lowered when the pool is covered - so I generally only mess with that number. Right now it is sitting at 22% with a daily pump run time of 6 hours...

I just lowered it from 25% since my chlorine level jumped up to 8.5ppm - I would like to see it around 5-6ppm.

Just thought I would share as covered pools add a whole different set of challenges to meet the perfect water conditions...I would follow the suggestion from Matt above and bump your CYA up to 30 or even 40 and see how things behave. Good luck!

 

[Kingston331gt]

thanks for the tips...keep them coming.

"When you open the cover, the ORP voltage drops because the chlorine is destroyed by UV light" I thought so too, but this happens at night as well with no sun and only a crescent moon. The ORB drop is consistent and predicable day or night.

The probe is a gold tip type.

I had my CYA at 30, then reduced to because the more my CG would run, the lower my ORP was. I battled that for two weeks before I reduced the CYA to where it is. Now, atleast when the CG is running, the OPR goes up.

good to know I was off on the superchlorinating withing the cell. I was thinking that the high concentration of chlorine gas in a small space would do that before it dissolved in the the stream.

 

[JoyfulNoise]

thanks for the tips...keep them coming.

"When you open the cover, the ORP voltage drops because the chlorine is destroyed by UV light" I thought so too, but this happens at night as well with no sun and only a crescent moon. The ORB drop is consistent and predicable day or night.

The probe is a gold tip type.

I had my CYA at 30, then reduced to because the more my CG would run, the lower my ORP was. I battled that for two weeks before I reduced the CYA to where it is. Now, atleast when the CG is running, the OPR goes up.

good to know I was off on the superchlorinating withing the cell. I was thinking that the high concentration of chlorine gas in a small space would do that before it dissolved in the the stream.

The thing to understand about ORP is that the voltage detected by the probe is affected by every chemical species in the water. Some of those chemical levels change slowly with time while others can change on an hourly or daily basis. Even certain chloramines can affect ORP levels. So it’s not unsurprising to see diurnal changes in ORP. Have you done an OCLT to determine if something isn’t growing in your water? Overnight loss of chlorine should be less than 1ppm and if it is more than that, then you’re battling two problems at once.

The question to answer is this - what does the ORP signal even mean in swimming pool water?

Sure, the ORP correlates to the FC level, but it is not exact. There have been many studies that have shown ORP probes showing a signal level of >750 mV but the solution only has minimal amounts of FC in it. Then other solutions that show ORP signals less than 700mV with high levels of FC. These variations happen between different probe manufacturers and even within the same line of ORP probes. So, in order for you to specifically know what your system is even doing, you have to map out the correlation of FC to ORP signal over a short period of time (how they vary within a given day) as well as the long term trend. Then you might actually have the ability to know with some certainty what your pool water is doing. While it is generally accepted that an water sample with an ORP signal >700mV is considered “sanitizing” that is only true under very carefully controlled circumstances and, in particular, when a strong oxidizer buffer like CYA is not present.

I understand your frustration as these ORP systems are sold as “turn-key” automation systems that are supposed to make pool care a snap. In reality, these systems cause more frustration and confusion then just simply running an SWG in duty-cycle mode and testing regularly to keep FC in line. In theory they sound great but in practice they are more trouble than they’re worth.

Sorry, I’m sure that’s not at all what you want to hear but, in my personal opinion, I’d write the thing off as a $1,200 mistake, and just use the pH control portion of it while the FC is controlled through manual changes in % output. Even the pH probe side of it can go bad and they usually only last a season or two before needing replacement so be sure to calibrate and check that regularly so that your pH doesn’t get away from you.

 

[tim5055]

Sorry, I’m sure that’s not at all what you want to hear but, in my personal opinion, I’d write the thing off as a $1,200 mistake, and just use the pH control portion of it while the FC is controlled through manual changes in % output. Even the pH probe side of it can go bad and they usually only last a season or two before needing replacement so be sure to calibrate and check that regularly so that your pH doesn’t get away from you.

I remember one member reporting last year that apparently his pH probe went and overnight injected his entire tank of acid into the pool.

 

[JoyfulNoise]

I remember one member reporting last year that apparently his pH probe went and overnight injected his entire tank of acid into the pool.

The Pentair unit would not do that. They have a hard-coded daily volume dispense limit that wouldn’t allow the pump to put out all the acid even if the probe fails. As you say, it’s done for safety reasons to protect the pool. It even shuts off the pH dispenser if the controller goes into SPA mode to protect people in the spa from too low a pH. Can’t speak for other control systems though....

 

[Kingston331gt]

Thanks for the input. We can all consider this a closed thread now.

Tim

 

[dradam]

Hi, sorry I did not see your post last year. I have been using the intellichem for about 6 years and please check out my diy automation articles. I hope they help.
When it works nicely it is a lot of fun to have, but there are imperfections and subtleties that can make it frustrating.

To get consistent readings:

I try to keep my pool at a consistent temp.
I run my pump 24/7 but at the lowest energy settings.- more time for the system to do what it has too.
Very minimal cya-- less than 30.
High sensitivity on the ph probe.
Keep orp a little on the high side-- when the cover opens it can drop quickly due to uv.
I add low level borates (about 2 boxes 20mule team ) per season. I find it helps stabilize PH even better.

Get used to your numbers-- especially when opening and closing the cover. The PH shifts with off gassing ect will be corrected when the cover closes. Get to know your own ORP number at the correct FCL level. The absolute number is less important then how it consistently correlates with your FCL. If you are in doubt about your ORP probe readings- may need to replace it or the cable. the cables fail too. If that fails could be the motherboard which is replaceable.

Hope you will find this and that it helps.

 

[dw886]

..may need to replace it or the cable. the cables fail too..

My pH cable failed over winter. When I fired up the system, it said my pH was 10. I swapped cables from my ORP sensor, and the pH reading dropped to 7.62 which was what manual testing showed, and using the pH probe on the ORP sensor caused it to go wonky showing my ORP at 400. I ordered a new cable, and have the pH dispense times / limits so low that it won't dose acid until I get a new cable. Interesting twist is that now after 3 days, it suddenly decided to start working and is now reading normal, but I don't trust it...

There's daily limits on acid dosing which are configurable. I had mine set low, and I caught this right away. If I hadn't, my daily limit would have kicked in and prevented it from dosing the entire acid container. If the limit was set high, you could dose much, much more than you wanted...

ORP scares me. I've come to the conclusion that ORP with autocover makes it even less reliable. I've seen my ORP values creep up over time of not using the pool causing my set point to become lower than ORP, and my FC to drop enough to where I needed to slam - if we go on vacation and don't open the pool for a week, I'm always nervous. I've also seen where ORP has dropped over time, and caused it to overdose the pool and make my FC higher than what I wanted...

Couple the above inconsistencies with the fact that a summer pool party with low CYA puts us at risk, it's not a science experiment for someone that doesn't like constant tinkering and monitoring...

 

[dradam]

Thanks for your comment. Yes, the system bears watching but I have found the opposite. When I am away with cover closed I have found excellent maintainence of PH and ORP. Thats the whole reason I got it in the first place. I am just now replacing the ORP Probe after 6 years. Low CYA does make the FC drop quickly for pool parties, If I know there will be a heavy bather load I will up the orp the night before to increase fc or worse case add some chlorox (BBB).
Nothing is truely "trouble free" But I do enjoy the tinkering and monitoring.

 

[jonpcar]

Dradam, do you just have the standard Intellichem ORP probe in your system? It sounds like you know your system very well and understand its limitations. Do you think that by analyzing historical graphs of ORP provided by intellichem and correlating those to known free chlorine (FC) tests and other factors, you could interpret that information (highs/lows/changes/timing/trends/temp/??) to provide more accurate triggers for chlorine injections? Or possibly just alerts to indicate FC is WAY out of whack (especially 0, haha)? Just wondering how smart the Intellichem ORP logic is as compared to what might be possible when someone “knows” their specific pool very well.

 

[dradam]

I may get in over my head here: As you know ORP is only only a correlate to the FC in the pool, not a direct measure. ORP--in my underdstanding may be afected by other ions and things in the water, ph, temp etc. Therefore I can only judge the FC based upon a relatively steady state in my pool. For those reasons I try to keep constant temp, 24/7 circulation and minimal chemicals (low cya if at all). At the begining of each season I correlate FC with the orp reading. It may indeed be different from one year to the next. I don't have a historical record. I believe the probe may age and give different readings season to season. So the baseline Orp is of value to me only in that season. If the numbers don't make sense I may have to adjust the baseline during a season. I set alarms if the ORP does go out of range. I do think Iknow my pool pretty well, to me this is a backup and does not replace periodic test strips. It is my understanding the FC probes do exist, but are extremely expensive. It would be nice if we had that direct measure.