- May 3, 2007
- 18,075
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
If you move the handle up above the stops, you partially close off the center pipe.
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SWG run time calculations assistance
- Thread starter sbcpool
- Start date
My valves don't work like that. They only swing 180°. If you're standing in front of them, right is the spa and left is the pool. Anything in between is some combination of the two with the middle presumably 50/50.
After 1 hour the FC hasn't changed. Not surprising in the noonday sun, but that means it's producing FC at about the same rate it disappears, which is about 0.2 per hour. 
I will leave the return plugged when the pump runs tonight, but I'm not hopeful.
I will leave the return plugged when the pump runs tonight, but I'm not hopeful.
This is video of how the returns look now with one of them plugged:
Sorry about the mustard algae on the walls. It's starting to come back because even running the pump for 8 hours is not generating enough FC. I brushed it off after noticing it in this video.
Sorry about the mustard algae on the walls. It's starting to come back because even running the pump for 8 hours is not generating enough FC. I brushed it off after noticing it in this video.
I've recently had similar issues with my SWG not producing anywhere near enough chlorine. After debugging with the manufacturer, we concluded that the issue was too high a flow rate through the cell. I too have a single speed pump, but I already had a bypass plumbed in, just the bypass valve was closed. Now I run with the bypass valve completely open, resulting in only a small proportion of the water going through the cell (bypass is straight, cell is on a "detour" with 4 90 degree bends. And I see much better chlorine production.
I still need to tune in the run time, and I have not yet verified that the SWG produce the amount of chlorine the manufacturer says - but it is *much* better than it was before.
All in all I think the bypass idea have a lot of merit.
I'm thinking about trying that route. It's a very tight fit on the equipment pad so any bypass will be limited to about 16 inches total length, including the cell. I also have to figure out how to regulate the flow in the bypass in such a way that the flow switch that isn't in the bypass cannot be triggered while there's not enough flow in the bypass.
I'm thinking of something like this:
My reasoning is that there's no way to shut off flow to the cell that way.
I'm thinking of something like this:
My reasoning is that there's no way to shut off flow to the cell that way.
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That is essentially how mine is plumbed in.
Thanks. I'd be too scared to have those other ball valves on the off chance that someone shut off flow to the cell while the flow switch was on.
Unfortunately, or fortunately, depending on how you look at it. All of this might have been for naught. Yesterday I ran a test that showed zero FC production but I just assumed it was because of the noon sun. I tested my FC last night after the pool was in shade and again this morning, which also showed zero FC production overnight. The control unit still shows only a power light and a generate light, and bubbles are coming from the cell and the returns. I'm testing now to make certain, but I think the cell may have gone kaput. I just don't know how it can be passing current through the cell and not producing chlorine.
Unfortunately, or fortunately, depending on how you look at it. All of this might have been for naught. Yesterday I ran a test that showed zero FC production but I just assumed it was because of the noon sun. I tested my FC last night after the pool was in shade and again this morning, which also showed zero FC production overnight. The control unit still shows only a power light and a generate light, and bubbles are coming from the cell and the returns. I'm testing now to make certain, but I think the cell may have gone kaput. I just don't know how it can be passing current through the cell and not producing chlorine.
Oh man! The worst part is I can't even send the cell back if it is dead, not until I replumb everything with the new unions they sent. The current collars won't thread on the bypass cell.
The extra ball valves are mainly there so I can isolate the circuit in case I need to remove the cell.
If it produce bubbles, I don't see how it cannot produce chlorine.
Are you sure, it is not because the FC is consumed faster than it can be produced ? You mentioned you had issues with mustard algae at some point ?
I ended up with near zero FC due to the SWG issues, and ended up with some algae, that confused the situation a great deal. I just completed a SLAM, and is now trying to dial in the SWG after that.
I'd suggest you do a SLAM using liquid chlorine, and once you're sure you got the FC consumption under control, then re-verify if it produce chlorine or not.
Certain. I've done OCLTs several times in the past couple of weeks. The mustard algae doesn't seem consume chlorine the way "regular" algae does (if it did it would be dead). It's always lying in wait for FC to dip below 6 or so.
As soon as it does, bam it's back. I don't care how many SLAMs with mustard algae shocks you do, it still works the same way every time. You can snorkel the pool with a toothbrush scrubbing every return outlet, nook, cranny, crack, skimmer box, and spa overflow and it will be gone for a while, but if that FC goes below 6 it comes back within a week or two.
The cell is still producing chlorine. It just increased the FC in the spa by 4 in 30 minutes.
For reference, here's a video of the cell while it's on. I don't know if there's anything you can tell by looking at it, but I guess it doesn't hurt.
For reference, here's a video of the cell while it's on. I don't know if there's anything you can tell by looking at it, but I guess it doesn't hurt.
In aquaria we have a similar engineering problem to solve, but dissolving CO2 gas instead of Cl2. The answer is a CO2 reactor. I'm wondering if the same concept modified for pool use would be of any utility. I'm thinking of a bypass followed by a vertical chamber of 6-inch PVC with flow from top to bottom. The water velocity in 16 inches of 6-inch pipe should be about 1/16th the rate of 2-inch pipe for the equivalent flow rate. In terms of dwell time it's like adding 21 feet of 2-inch pipe to the system. The downward flow should keep more bubbles in suspension longer. That should allow the Cl2 more time to dissolve. I just don't know if the results would be worth the trouble, and how to experiment with it in a way that's easy to fix if it doesn't work out.
- May 3, 2007
- 18,075
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
The top of the cell has no bubbles correct?
That seems very excessive and would explain the reduced efficiency. I don't think the cell is working properly.
One additional thought, you could take the cell to a pool store and have them test it.
That seems very excessive and would explain the reduced efficiency. I don't think the cell is working properly.
One additional thought, you could take the cell to a pool store and have them test it.
There are no bubbles in the top of the cell.
What could cause excessive bubbles if the current and amperage are within spec?
What could cause excessive bubbles if the current and amperage are within spec?
- May 3, 2007
- 18,075
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
It may not be wired correctly internally or there is a short between the plates.
I would have a pool store test the cell if they can.
I would have a pool store test the cell if they can.
I have a Fluke 88V. I can test if I know what I'm looking for, unless there's a test I can't do with that.
- May 3, 2007
- 18,075
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
About the only thing you could do is to measure the continuity at the cell plug between the power ports (if you know which two they are). It should be infinite. Measuring continuity between plates is nearly impossible given the spacing plus there is a chance of damaging the surface.
- May 23, 2015
- 25,704
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
You want to be very careful with this idea. The bubbles are mostly hydrogen gas and if they build up in the top of this reactor and form a gas pocket, you can creat least a detonation/explosion hazard. Chlorine/Hydrogen gas mixtures are unstable and easily detonated; there are many pictures online of SWGs that were not plumbed properly or ran without flow and exploded. The gas bubbles need to exit the water at the returns.
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I guess I won't try the reactor idea. I don't want to create any dangerous conditions.
Since it's easier than everything else, I'm going to pick up some 3/4 - 1/2 reducer bushings when I go get supplies for replumbing the cell unions. Since they insert into 3/4 pipe they should reduce flow just like an eyeball. That will eliminate that variable.
Since it's easier than everything else, I'm going to pick up some 3/4 - 1/2 reducer bushings when I go get supplies for replumbing the cell unions. Since they insert into 3/4 pipe they should reduce flow just like an eyeball. That will eliminate that variable.