Has anybody had problems with the CircuPool union collars not fitting the bypass cell? They thread onto the real cell just fine, but they will not thread on the bypass cell more than a half turn before they bind. I thought maybe it was just dirty and cranked it with my hand a little and it took putting it in the hot water to get it off. The threads are clean and free of burrs or visible defects. The thread pitch is not obviously different, but neither collar will thread whatsoever.
Can't Screw Collars to CircuPool Bypass Cell
- Thread starter sbcpool
- Start date
- Jun 22, 2014
- 47,789
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
I've not heard of that issue before, but as we know it only take a minor defect in the manufacturing process for something to give us a problem. 
Last thing you want to do is damage the union collar. Where did you purchase your bypass?
Last thing you want to do is damage the union collar. Where did you purchase your bypass?They came from discountsaltpool.com along with the RJ60+ unit. The nearest I can tell is that the crests on the bypass cell's threads are a little "fatter" than the crests on the CircuPool cell's threads. I could see how they might bind if the roots on the collar's threads are narrower. Maybe the thread angles are a little different. Hard to say.
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- Jun 22, 2014
- 47,789
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Crazy. You've really had a rough time with this product. Hope this issue gets resolved soon to your satisfaction.
Thanks. I'm used to it. My friends joke about how I have the worst luck this way. They joke that they won't go shopping with me because they don't want broken stuff. If one in a thousand products is a dud, I'm the guy who ends up with it.
Looks like the threads are different. Look at the difference in the crests of the threads and that underside of the threads.
- Jun 22, 2014
- 47,789
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Pretty good comparison. Curious to hear what your friends at DSP have to say. 
Hey SBC - sorry about your luck with the RJ...
To answer your question from your first post: Also purchased the by-pass cell from DSP when I order my unit last year. Use mine when I winterize. Fit no issue, and I ran with it for about a week at the start of this season.
The threads on my rings are the same as the threads on a Charlotte pipe threaded 2" adapter. These were the fittings on either end of the by-pass pipe I received.
To answer your question from your first post: Also purchased the by-pass cell from DSP when I order my unit last year. Use mine when I winterize. Fit no issue, and I ran with it for about a week at the start of this season.
The threads on my rings are the same as the threads on a Charlotte pipe threaded 2" adapter. These were the fittings on either end of the by-pass pipe I received.
That gave me the idea to test whether the bypass will thread into the cleaning stand I also purchased. It's a little tight, but it does thread. On closer examination I suspect the issue is that the threads on the bypass are slightly misaligned where they joined two halves to make the ends. If this is the cause, that's a slim margin on the tolerances between the CircuPool collars and the bypass.
I'm not sure how to thread a half circle of pipe or why it would make sense to thread it before welding the two halves together, though. But there they are, clearly two welded halves not quite aligned.
Either way, calling DSP now.
Those teeth edges look to be slightly rounded. The ones on my pipe come to a sharp edge.
My fittings do have mold marks for the two half's of the mold. But line up with each other. He is what my fitting look like.
My fittings do have mold marks for the two half's of the mold. But line up with each other. He is what my fitting look like.
After seeing yours I'm back to my original assumption that the threads on mine are too "fat." It's very different than yours. DSP is sending a new bypass and promised to test it first. I'll post here when it arrives.
UPS just delivered the replacement bypass cell. It will not thread either. It's the same story: a half turn and it binds. It feels exactly like it's cross-threaded, except it's not.
I'm wondering if CircuPool has changed the threads slightly. I've given some serious consideration to an id-10-t error, but if the issue was me I wouldn't think I'd be able to thread the cell so easily like butter smooth. I also would expect not being able to thread the bypass on the cleaning stand with zero effort, but that's not a problem either. I have tried upside down and sideways a half-dozen times and I guarantee that these union collars will not thread onto these bypass cells.
Now I'm more worried about what I'm going to do if the cell is out of service than I am about getting settled up with DSP. Maybe I have to order a bypass cell directly from CircuPool?
EDIT - I just noticed the big difference in the threads, and I can't believe I didn't notice it until now. An image is worth a thousand words.
There are large flat bottoms in the valleys of the thread grooves on the real cell, but not on the bypass cell. Instead the bypass cell's threads have the flat area at the peaks, where you would expect them on a mating thread's profile (like the collar's).
I'm wondering if CircuPool has changed the threads slightly. I've given some serious consideration to an id-10-t error, but if the issue was me I wouldn't think I'd be able to thread the cell so easily like butter smooth. I also would expect not being able to thread the bypass on the cleaning stand with zero effort, but that's not a problem either. I have tried upside down and sideways a half-dozen times and I guarantee that these union collars will not thread onto these bypass cells.
Now I'm more worried about what I'm going to do if the cell is out of service than I am about getting settled up with DSP. Maybe I have to order a bypass cell directly from CircuPool?
EDIT - I just noticed the big difference in the threads, and I can't believe I didn't notice it until now. An image is worth a thousand words.
There are large flat bottoms in the valleys of the thread grooves on the real cell, but not on the bypass cell. Instead the bypass cell's threads have the flat area at the peaks, where you would expect them on a mating thread's profile (like the collar's).
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Contacted CIrcuPool directly and they also shipped a bypass cell at no charge (kudos to CircuPool). Unfortunately, just like the other two, it does not fit the collars. I am now looking at replacing the collars, which is unfortunately going to involve more plumbing work than I'd like since there isn't enough pipe left to cut them out and repair with couplings. I'm going to have to repipe everything from the heater to the diverter valve.
I am going to ship back the three bypass cells and request that they ship new collars already screwed down tight onto a bypass cell. If I still have problems I know I'm the one with the problem.
I am going to ship back the three bypass cells and request that they ship new collars already screwed down tight onto a bypass cell. If I still have problems I know I'm the one with the problem.
- Jun 22, 2014
- 47,789
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
They are shipping new collars, but were not willing to to have me send the dummy cells back and return one of them with the collars already threaded. Fingers crossed that the collars are the issue.
Rattus Suffocatus
Silver Supporter
- Jun 5, 2019
- 1,657
- Pool Size
- 14000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool Universal40
Interesting. I was the oddball who bought a "Universal40" -- old school unit.. and I bought and did all of the plumbing with the dummy in place before putting in the cell. The dummy cell for that unit looks like it was hand made out of hardware store parts but fits just like the real thing. Interesting that this is happening. I wonder if it's a classic case of metric vs imperial "close enough" not being.
If they are super close you could probably re-thread the dummy cell with a die of the correct size....
If they are super close you could probably re-thread the dummy cell with a die of the correct size....
Part of me wants to cut the collars in half so I can examine the thread profile carefully. I may just take one to the hardware store and see if I have a problem threading it onto a union.
One side of my edge is hard to turn when removing the cell..The bypass is also hard to turn but nothing I can't deal with since I may never remove it. But something is cut off slightly
That's what bugs me - the cell itself threads so smoothly you can spin the collars on like a wing nut. It's just the bypass cells that won't work.