Re-plumbing question

danc58

Silver Supporter
May 26, 2020
18
Long Island, NY
Pool Size
35000
Surface
Vinyl
Chlorine
Liquid Chlorine
I've got a question about plumbing that I have not been able to find a direct answer to.
Short story long, we are re-doing our pool patio after 18 years. Original was concrete with paver bullnose coping. New will be pavers with bluestone coping.
Pool is 18' x 38' rectangle with an 8' ell, steps at the end of the ell. There are two returns on either side of the steps, and two more on the main section of the pool directly opposite the skimmers, 38' away.
Original pool build PB used 1-1/2" flex pipe for all of the plumbing, which is now 18 years old. I've heard some scary stories about the flex pipe possibly being damaged by insects, and since the old deck is removed, it seems like a good idea to take advantage of the situation and replace all of the plumbing now (another while you're in there moment...).
Anyway, I plan on replacing all of the 1-1/2" flex with 2" rigid PVC, and my question concerns the returns. As currently plumbed, there are two 1-1/2" return lines coming from the pad, one to the steps, the other to the main returns. Each of these two lines connects to two eyeball returns. My plan is to do similar, but the question is how to split each of those two return lines into two eyeball returns?

I have one guy who wants to use a tee for each pair of eyeballs, but he wants to run the return line centered between the eyeballs, into the base of the tee (the branch connection), and then run each end of the tee (run connections) out to each eyeball.
I've been led to believe that this is NOT the proper way to use a tee, but I haven't been able to find any specific reasons why not to do this.

View attachment 176947

I'm more inclined to do this (below), but then I think I'll have an imbalance, with the right return getting about 20% more flow than the left port will get. This port will be toward the steps, so the other two returns will be flowing perpendicular to these. Same situation applies by the steps.
View attachment 176949

Any thoughts or opinions?
Thanks.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,877
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Your pics did not get attached. Give it another try.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
37,099
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
To balance returns you need to loop the line to the returns.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
37,099
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
They will not balance that way. You have to loop the line back to itself after the returns to balance.
 

danc58

Silver Supporter
May 26, 2020
18
Long Island, NY
Pool Size
35000
Surface
Vinyl
Chlorine
Liquid Chlorine
Like this?
Seems like that will create quite an increase in head, almost five-fold if my calculations are anywhere near correct.
1614188191619.png
 

danc58

Silver Supporter
May 26, 2020
18
Long Island, NY
Pool Size
35000
Surface
Vinyl
Chlorine
Liquid Chlorine
So my REAL question (which kind of got lost in my original post) is about the use of a TEE.
One installer says to use one tee for each pair of eyeballs, centered between them, with the main return water line going into the branch (bottom) connection of the tee, and then feed out to the two eyeballs with equal length pipe and fittings.
1614201134978.png
I've been led to believe that this is NOT the proper way to use a tee, but I haven't been able to find any specific reasons why not to do this.

Any comments on that?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
37,099
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Any comments on that?
One of our builder members will have to respond to that.
On the loop, the water pressure balances throughout the system. There is no additional head loss.
 

danc58

Silver Supporter
May 26, 2020
18
Long Island, NY
Pool Size
35000
Surface
Vinyl
Chlorine
Liquid Chlorine
Hey all.
In-ground pool, replacing the 18 year old 1-1/2" flex pipe, and liner, wanting to use 2" schedule 40 PVC pipe all around. I have a few questions, hoping a pool pro might help me out.

1. Skimmers are Hayward SP10851OM. According to the drawings, there are two outlets, one (rear) is 1-1/2" FIP, the other (front) is 2"(rear) FIP. Fronts (2") are plugged, not used in my pool, since we have a completely separate main drain; no equalizer. Question is, if the front outlet IS actually 2", is there any good reason why I shouldn't use the front 2" outlet back to the pump, and plug the 1-1/2"?

2. This actually applies to both the 1-1/2" and the 2" outlets...
Should I go straight MIP x socket adapter, then a 90 elbow, or use a MIP x socket 90?
If I CANNOT use the front 2" outlet, and therefore have to stick with the 1-1/2" outlet, I will need to transition to the 2" pipe. What is the best method for doing so? Here are a couple of what I consider to be my options...
a) 410-015, elbow, 1-1/2" male thread by female socket, 1 short piece of 1-1/2" pipe, then a 429-251, 2" x 1-1/2" Reducer Coupling to transition to the 2" pipe.
or
b) 436-015, 1-1/2" Male Adapter (thread x socket), then a 406-251, 2" x 1-1/2" 90° Elbow. From there to the pump, all 2".

3. Returns - any reason not to use Wyes (475-020 for 2") instead of Tees where I split a single 2" return line between two 1-1/2" eyeball inlets? They're not cheap, by also not crazy expensive, since I'll only need two (two return lines, four eyeballs). I would think the flow characteristics of the wye would have to be more evenly matched than a tee, even though still not perfect.

4. Pump, filter, chlorinator INs/OUTs are all 2". Is there any advantage to running 2-1/2" piping and valves at the pad, rather than 2"? I would need quite a few adapters, which I suspect could potentially offset any gains from using the larger pipe.

Any suggestions are welcome.

Thanks.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,877
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
First of all the minor flow stuff you are asking about will make no visible difference in your pool operation. Do whatever is easiest for you.

1. Skimmers are Hayward SP10851OM. According to the drawings, there are two outlets, one (rear) is 1-1/2" FIP, the other (front) is 2"(rear) FIP. Fronts (2") are plugged, not used in my pool, since we have a completely separate main drain; no equalizer. Question is, if the front outlet IS actually 2", is there any good reason why I shouldn't use the front 2" outlet back to the pump, and plug the 1-1/2"?

Use whichever size matched the line to the pump suction.

2. This actually applies to both the 1-1/2" and the 2" outlets...
Should I go straight MIP x socket adapter, then a 90 elbow, or use a MIP x socket 90?
If I CANNOT use the front 2" outlet, and therefore have to stick with the 1-1/2" outlet, I will need to transition to the 2" pipe. What is the best method for doing so? Here are a couple of what I consider to be my options...
a) 410-015, elbow, 1-1/2" male thread by female socket, 1 short piece of 1-1/2" pipe, then a 429-251, 2" x 1-1/2" Reducer Coupling to transition to the 2" pipe.
or
b) 436-015, 1-1/2" Male Adapter (thread x socket), then a 406-251, 2" x 1-1/2" 90° Elbow. From there to the pump, all 2".

I don't fully visualize the problem but I say do whatever is easiest. You are not going to see a difference for additional effort.

3. Returns - any reason not to use Wyes (475-020 for 2") instead of Tees where I split a single 2" return line between two 1-1/2" eyeball inlets? They're not cheap, by also not crazy expensive, since I'll only need two (two return lines, four eyeballs). I would think the flow characteristics of the wye would have to be more evenly matched than a tee, even though still not perfect.

I would use T's and not try and be fancy.

4. Pump, filter, chlorinator INs/OUTs are all 2". Is there any advantage to running 2-1/2" piping and valves at the pad, rather than 2"? I would need quite a few adapters, which I suspect could potentially offset any gains from using the larger pipe.

No. 2" in all the equipment pad is plenty good.
 

Enjoying this content?

Support TFP with a donation.

Give Support

danc58

Silver Supporter
May 26, 2020
18
Long Island, NY
Pool Size
35000
Surface
Vinyl
Chlorine
Liquid Chlorine
Haven't gotten any further responses on this, so I thought I'd chime in on some other info I found here.
In this post Plumbing Configurations it looks like tees are being used in numerous locations with the "branch" as the inlet. I know those are only diagrams, but I don't see any other way to accomplish what is shown.

Maybe that validates the idea of using the branch of the tee as the inlet?
 
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.