What is the thread size on a “Jandy Universal Union”?

Sampo

Gold Supporter
Aug 19, 2022
77
Southeast PA
Pool Size
34000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-60 Plus
Does anyone know the thread size for a “Jandy Universal Union”?

As background, I plan to remove the Nature2 Fusion that was installed with my pool -- since it isn’t used and since it might be adding some resistance to flow. But rather than cutting out its unions, I’d like to preserve the connection (to swap in a SWG in the future, for example). The Nature2 specs referred to the connection as “our standard 2" x 2½" Universal Union“. Since my pipes are 2” PVC, I assumed that meant that the Fusion side of the connection was 2.5” mpt and that a standard PVC SCH 40 fitting would fit. But that didn’t work! On inspection, the connection seems to measure closer to 3”, or maybe a touch more. Does anyone know if a 3” mpt thread would interface with their connection? If not, where can I find a male end that will fit?

Thanks, and “CYA later”

Sampo
 
Does anyone know the thread size for a “Jandy Universal Union”?

As background, I plan to remove the Nature2 Fusion that was installed with my pool -- since it isn’t used and since it might be adding some resistance to flow. But rather than cutting out its unions, I’d like to preserve the connection (to swap in a SWG in the future, for example). The Nature2 specs referred to the connection as “our standard 2" x 2½" Universal Union“. Since my pipes are 2” PVC, I assumed that meant that the Fusion side of the connection was 2.5” mpt and that a standard PVC SCH 40 fitting would fit. But that didn’t work! On inspection, the connection seems to measure closer to 3”, or maybe a touch more. Does anyone know if a 3” mpt thread would interface with their connection? If not, where can I find a male end that will fit?

Thanks, and “CYA later”

Sampo
They are "universal' in the Jandy universe of products. They are a proprietary thread and size, as are other manufacturers' products.
 
Jandy unions use a proprietary thread so you pay the Jandy tax on their equipment.
 
Ha ha! "I am universally loved... in my own Universe" -Jandy

Ok, sounds like I need the OEM part. Does anyone happen to know where to find just the male component? My initial searches yielded just "half unions" with the tailpiece.

cary elwes GIF
 
Ha ha! "I am universally loved... in my own Universe" -Jandy

Ok, sounds like I need the OEM part. Does anyone happen to know where to find just the male component? My initial searches yielded just "half unions" with the tailpiece.

cary elwes GIF
I think Jandy just sells the kit. They want their price even if you just need one piece.
 
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With no automation, you're free to go with another manufacturer. The biggest Jandy SWG only creates 4.4 FC per 24 hours in your 34k pool.

While that's plenty in the northeast, name brand cells last about 10k hours on/producing and you'll reach end of life sooner when it runs almost all day everyday. Bigger cells (in this case from a different manufacturer) don't cost as much as the lifespan they add so the maths works great in your favor.

A circupool RJ-60 for example will put out over 2.5X the FC per day of the Jandy, running over 2.5X less, living over 2.5X longer. With Jandy being spendy and only available from pool stores / builders, it may even be the same price as the Circupool, or at least close. A no brainer any way you slice it.
 
Aww, heck. We're buddies now. And you quoted Mr Montoya so I like you even more. (y)

*cracks knuckles*

Here's the bleach vs SWG comparison for 34k gallons.

10% liquid chlorine is 2.9 FC for you.

$5 jug = $1.72 / FC
$6.01 jug = $2.07/ FC (PA Walmart / 6% tax)
$8 jug (lowes) = $2.75 / FC
$9 jug (HD)= $3.19 / FC.

A circupool RJ60 will make 11 FC per 24 hours, or 4583 lifetime FC, conservatively using 10k hour life and not the 15k they claim. So the conservative estimate equals 1580 gallons of 10% liquid chlorine for you.

If purchased at Walmart, they'll cost you $9495.80 out the door. I don't even care what the SWG cost or what you pay someone to install it. It's $1800 for the unit, maybe up to $3k for a full install and even then it's over 3 times cheaper than bleach.

The first ($3k) cell will produce at $0.65 per FC. If you DIY the install it'll be $0.50 per FC because you need about $500 in parts to install it. Replacement cells don't need the pro labor, electrical parts / timer or the control unit and are about $400 for the same absurd amount of FC, at an even more absurd $0.09 / FC.

So to recap :

Walmart 10% = $2.07 / FC
Full install RJ60 = $0.65 / FC
DIY RJ60 = $0.50 / FC
Future RJ60s = $0.09 / FC

None of this puts up to $3k in the available funds bucket, but the sooner those funds are one day available, the more money you'll have in the long term. You could pay credit card interest making payments on the $3k and still clean up.

*edit. I still can't believe the RJ60 replacement cells are $400 direct from Circupool. I'm almost certain they were $800 recently so maybe it's a pre season sale. But even if we double the cost to $800, future cells produce at 18c per FC and it's 11.5 X cheaper than Walmart 10%. That's insane.

Don't even get me started on the convienence of *not* lugging 1580 jugs per cell. I waltz out back and press *1* button and more chlorine shows up in the pool. Then It doesn't need another button push for 2 to 6 weeks.
 
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Wow! This is incredible analysis — thank you!! The economics of the SWG totally blast my Stenner out of the water!

Still, the one possible catch for me is my worry about the feel of the water. I grew up swimming in small lakes — and my pool outside of a city is my way of looking back on that time. Maybe it’s crazy nostalgia, but I really worry about any extras (both salt/SWG and borates) changing that feel — even when I objectively know that they’d ease my chemistry management. That was the deciding reason why I went with the Stenner over a SWG last year. Yet, if I’d seen your numbers then, I would have been even more torn!

On the other hand, I know that all the bleach that I’m dumping in is undoubtedly moving my salt levels up anyway. Now that I’ve seen your analysis, I’ll definitely check my salt reading when I open at the end of next month: maybe I’m already close and didn’t even know? If it wasn’t for my worry over changing the feel/taste of the water, the SWG would be installed in a heartbeat. In the meantime, I’ll definitely be measuring the potential fit for the RJ60 where my Nature2 currently sits (the DIY part shouldn’t be a problem if I pull that trigger). Great recommendation!

Once again THANK YOU. I’m totally blown away at the depth of your response.
 
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A pool with a SWG contains chlorine and salt.

A pool with liquid chlorine contains chlorine and salt.

There is NO difference in the water feel between the two if water chemistry is kept with TFP recommendations.

NONE!
 
The economics of the SWG totally blast my Stenner out of the water!
And the SWG comes 'pre-filled' with 1580 gallons of chlorine. :shock:

Even if you got free delivery you'd still have to carry those jugs around back and add 1580 jugs to the stenner tank.

Or *zero jugs* for 3X less then 11.5 X less.

I can't even. :laughblue:
I’ll definitely be measuring the potential fit for the RJ60 where my Nature2 currently sits
Do not be constrained by what you currently see. If need be you can add a loop, either vertical, front / back or left / right. A couple of 90s won't make a noticeable difference in flow.
I’ll definitely check my salt reading when I open at the end of next month: maybe I’m already close and didn’t even know?
We have short seasons and lots of rain so you'll have less than most of the counrty would. But it'll be alot more salt than none.

FYI, people about 9000 ppm salt and theoretically that would feel the best. The 3500 of the salt pool will (maybe) feel better than the 1500+ of a LC pool, but it won't feel worse. And it totally feels nothing like the 35,000 ppm ocean.
 
Still, the one possible catch for me is my worry about the feel of the water. I grew up swimming in small lakes — and my pool outside of a city is my way of looking back on that time. Maybe it’s crazy nostalgia, but I really worry about any extras (both salt/SWG and borates) changing that feel — even when I objectively know that they’d ease my chemistry management.
FWIW, many people report superior "feel" of water with salt at SWCG levels. We've even had a couple of threads asking whether it's okay to add salt in LQ pools. Me, I'm skeptical that people can actually sense differences among TFP-compliant waters. But whatever makes the owner-maintainer happy...
 
Me, I'm skeptical that people can actually sense differences among TFP-compliant waters
I used to think the salt made a big difference, but when we built pool #2 I had the typical delay to SWG and got to swim in a TFP liquid chlorine pool for several days. I could not tell the difference and they were equally nice. Maybe some feel it a little, maybe it's a placebo. But it turns out every pool I'd ever been in was out of balance so they felt like they did.

Both my SWG and LC pools on TFP felt amazing.
 
I confirmed that a Circupool RJ-60 SWG cell would [just] fit in the spot for my Nature2. Pic below. For reference, flow out of the filter comes horizontally towards the viewer in the pipe with the blue circle, then leftwards/downwards in the diagonal segment, turns 180, flows rightwards through the Nature2, and finally away from the viewer in the pipe with the green and red circles. The red circle indicates the existing port for my Stenner system -- which is the last fixture in this setup. I do not have a heater.

I could keep the same configuration of the pipes -- although I'd have to repipe much of the same setup since the "universal" Jandy unions would need to go.

Two questions:

1) Would you recommend placing the Flow Switch for the SWG either in the blue circle (on the horizontal run upstream/proximal from the SWG cell) versus in the green circle (downstream/distal from the cell). Both locations have ~12" straight runs before the switch location, as specified in the User Guide. The blue spot would involve slightly more plumbing, and there would be an elbow immediately after the switch (the User Guide was silent on any limits downstream from the switch). The green spot would have the Stenner input immediately downstream. I also considered the diagonal segment for the flow switch, but based on the mechanics of the switch, I am assuming that wouldn't work (although the User Guide doesn't specify).

2) More generally, is there any issue with having an input from a Stenner tank downstream of a SWG? Not that one would be particularly needed, but since I've already made that investment I suppose that I'd still use the Stenner to supplement the SWG for any SLAMs or small adjustments... or maybe even convert it from bleach to acid (after washing out the system very carefully).

All this being said, I'm not yet 100% sold on the SWG. But the collective chorus on this forum is pretty overwhelming! I plan to start experimenting with salt in the Spring -- perhaps cautiously and gradually raising my salt level first before deciding to buy the SWG.

Spot for SWG?.png
 
Flow switches are to be installed horizontally or vertically with an upward flow.

Never install a flow switch vertically with a downward flow.

If the flow switch fails you want gravity to help it fail open. With a downward flow the flow switch can fail closed.

Flow switch can go before or after the cell. It makes no difference.
 
Got it. That's what I assumed, and ruled out the diagonally sloping segment. But are there any advantages to either the blue or the green positions -- both are horizontal?
 
I wanted to update that late last night I realized my screw up. The $400 replacement cell is the RJ-60 classic. You'll need the RJ-60 plus (one day). That one is $794 which would cost 18 cents per FC. (18.3 cents with tax) Boohoo. :ROFLMAO:
 
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