SWG Chlorine Generation too low

MITBeta

Gold Supporter
May 28, 2020
1,206
North Attleboro, Massachusetts
Pool Size
13000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
My new RJ-45+ isn't generating what it should. I just ran an Overnight Chlorine Gain Test and got less than half what I was expecting. This followed a mini-ONCL of about 4 hours where no chlorine was lost at all.

Background: This is my first season with a new RJ-45+ SWG. It's been running fine for 6 weeks or so. I have been slowly bringing CYA up to the SWG recommend level of 60ppm. In the past, my pool has consumed about 2ppm/day on average. This means I should be able to run at 30%and for 9 hours to generate >2ppm in a 13kgal pool.

We had a lot of people in the pool over Memorial Day weekend and my FC "crashed" down to 5.5ppm, which is still above target for SWG. I immediately added enough LC to bring the level back up over 10ppm. Then I ran an ONCL test with no loss found.

For the last couple of weeks I've found that I have to keep bumping the output percentage up, despite simultaneously increasing CYA levels. Last night I tested at 6.5ppm at 10:30pm, then ran the SWG on Boost (Max) for 9 hours. I was expecting to see 13+ ppm, but instead only got 9.5ppm, a 3ppm gain. I will run an ONCL test tonight to be sure.

Is it possible I'm only getting generation on 1 polarity? I've read many debates on phosphates having an effect on SWG production, but I've never tested for that. Am I somehow misinterpreting my expected generation? What else could be going on?

I'm going away in 9 days for 10 days and was really looking forward to not having to worry about chlorine additions. Now I'm worried and need to figure this out ASAP.
 
As I have posted elsewhere I am skeptical of some SWG manufactures claimed chlorine output.

Figure out what % generation setting it takes to maintain your FC level. Don't worry so much about what the calculated chlorine generated number ends up being.

Once you know your pool uses 2 ppm/day you can back into the SWG generation capacity once you know what % it takes to maintain your FC level. I think it will be closer to 1.4 then 2.0.
 
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I'm with Allen that some manufacturers blow more smoke than others. That said, you *still* have a beast of a unit that will hum along during the peak season.

Keep in mind that this is the time of year that the UV keeps increasing, requiring more production to match. Don't get too discouraged because believe me, when the season starts to wind down you will see the other side of it. 'I took a 3 day weekend away and my FC is a 19!!!!'

The season adjustments go something like :

Open, up, up, up, down, down, down, close.
 
MIT.

The Overnight Gain test was my idea, and it was really just to provide some confidence that the cell was working. I have no idea how accurate it is.

Just keep in mind that various testing errors could skew the results. Some cells have much longer on off cycles, so exactly when the test is started and stopped can affect the outcome.

In the big picture, it is not all that important that any cell produce exactly X output, as long as the cell will satisfy the amount of chlorine your pool needs each day.

Thanks,

Jim R.
 
Some cells have much longer on off cycles, so exactly when the test is started and stopped can affect the outcome.
I noticed on my RJ-30+ any setting bellow 50% has really long off cycles. Seems that starting at 50% the off cycles (if any) are barely noticeable. Running my system @ 50% over 6 hours seems to consistently produce 1 ppm of extra chlorine than running it @ 25% over 12 hours (tested on 6 different nights)… I didn’t have the patience to try increasing/decreasing the times to confirm my suspicion.
 
I'm SUPER thankful I learned mine pre-TFP. All I knew was that if 20% wasn't cutting it, to click the + sign once to 40%. It worked. I went about my life happy. Lalalalalalalala. You all are starting this with way too much knowledge making you micromanage it. :)
 
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I appreciate everyone's responses. I would be much more likely to accept the variance from rating theory if I was measuring more like 70%-90% of rating. But what I'm seeing here is closer to 45%.

I was very careful with the overnight test. I turned the pump on at high speed with the SWG off to ensure the water was well mixed to take my initial sample. Then I switched the pump to low speed and turned the SWG on. I pressed the Super CL button, which the manual states:

Temporarily boosts Chlorine Output to 100% Maximum Power for 24 hours

I let it run like that for 9 hours, then I shut the SWG off and switched the pump back to high speed for 20 minutes to ensure every last bit generated got mixed in. This should have generated 6.9ppm according to the specs, and there should have been no cycling because it was at 100%.

Keep in mind that this is the time of year that the UV keeps increasing, requiring more production to match.
My logs from last June say that I added 49.5ppm of LC over 30 days. That's 1.7ppm per day, and that was at a lower CYA. Right now according to the math, I have my SWG set to produce 2.8ppm per day and it's not keeping up. This difference seems to line up with the overnight gain test.

I run my pump for 7.5 hours per day, which is 2 full 180 minute cycles + the 40% of cycle 3 + a couple of minutes to push the generated gas out of the return pipe.


That said, you *still* have a beast of a unit
This statement is only true if it delivers its advertised rated output, or something close to it.

You all are starting this with way too much knowledge making you micromanage it.
I get what you're saying. But that's the other beauty of the TFP way. The fact that I can look back at a specific period in time and see what I added to my pool and what effect it had and then relate that information to the current situation is really empowering.

Any other thoughts on diagnostics I can run to see if there's a problem with the cell or if it's just grossly overrated?
 
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I wasn't able to run the ONCL test on Saturday, but I did run one last night. FC 9.5 at 10:30pm and FC 9.5 at 7:30am.

Which brings me back to my concern that this SWG is under performing by about a factor of 2. Is there anything else I can check before I go back to the manufacturer?
 
Which brings me back to my concern that this SWG is under performing by about a factor of 2. Is there anything else I can check before I go back to the manufacturer?
I believe you have done all you can to prove the cell is only producing half the time. It sure sounds polarity related IMO.

Fire away at Curcupool.
 

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I wasn't able to run the ONCL test on Saturday, but I did run one last night. FC 9.5 at 10:30pm and FC 9.5 at 7:30am.

Which brings me back to my concern that this SWG is under performing by about a factor of 2. Is there anything else I can check before I go back to the manufacturer?
I am considering purchasing the same CircuPool RJ45+, let us know what feedback you get from CircuPool.
 
Regarding Super CL mode, if you switch power off, boost mode is disabled. Just pointing this out because you mentioned you shut the unit off prior to testing:

Super CL: Temporarily boosts Chlorine Output to 100% Maximum Power for 24 hours, or until power is removed from the system.
Did you check diagnostics using the "menu" button. Not sure what value it has, but make sure numbers are in range. From the manual:

7) Menu: Press sequentially to cycle through the following information:​
1. Pool Temperature (xx degrees Fahrenheit or Celsius)​
2. Cell Voltage (often 21.0 to 27.0 volts when chlorine is being generated, otherwise 16-31V)​
3. Cell Current (often 2.50 to 7.80 amps when chlorine is being generated, otherwise 0 amps during normal rest cycles.)​
4. Real-Time Salinity reading ( xxxx PPM or x.x grams/Liter.)​
5. System ID​
6. Software revision level​
7. Cell Version.​

Make sure pump is running at a speed well-above the flow switch minimum speed. If it's right on the edge, the flow switch may switch on/off during the run cycle.

Hopefully you get it sorted out. I'll be watching as well.
 
if you switch power off, boost mode is disabled.
I know it was in Super CL all night because I had to turn it off in the morning to allow it to mix for 20 minutes or so before testing.

I checked the diagnostics during two consecutive cycles on Saturday. Unfortunately, only the 2nd saved in my notes. My recollection is that the other one was substantially similar. I was surprised that it didn't report negative voltage on one cycle or the other.

21.4v
4.65a
3550ppm
Make sure pump is running at a speed well-above the flow switch minimum speed. If it's right on the edge, the flow switch may switch on/off during the run cycle
I thought about this. I haven't even seen it kick off due to low flow (unless I was switching pump speeds or something like that). So I really don't have any way to monitor this. I thought about plugging it into an energy logger, and may still do that. I would have to figure out how much energy the unit uses when generating vs. not and then use that to figure out actual generation time.
 
So I really don't have any way to monitor this. I thought about plugging it into an energy logger, and may still do that. I would have to figure out how much energy the unit uses when generating vs. not and then use that to figure out actual generation time.
Just run the pump on high all night. It's not worth the headache for $8 in electric. Now. All month around the clock, yeah. Low speed is your friend. But for one night of testing purposes, let er rip.
 
I did run it all night. But I have no way of knowing whether generation stopped at any point because of low flow.
To confirm, you ran on high speed all night ? Low speed might be iffy, but high should have no problems.

I doubt the flow switch would consistently fail half the time under full throttle.
 
Ah, I see what you're suggesting. Light dawns on Marblehead
Low speed has already caused you some grief. I'm twice as fast to blame it this time.

How has the bubble fix been doing ? Are we complely moved on or still keeping an eye on it ?
 
I get a bubble in the pump lid when the skimmer sock is loaded up. With no resistance to suction flow, no air gets pulled in. Kids bouncing around in the pool also introduces air, but I can control for that.
 
You're having a marble head moment again. And it's ok old friend. Ask me how I know. :hug:

I meant the SWG bubble that caused a replumb. The original bubble leaving plates high and dry could certainly cause the production to suffer. How has the fix been working out for the SWG ?
 

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