Plumbing Question... Under construction

[DCFan9]

First I want to thank all of the members in the forum for sharing their knowledge and experience with pools, I have found the information very helpful in our pool project which I will post later today.

My question is this: should the skimmers use 2" PVC On the entire run?

We are building a 41' x 21' free form gunite pool with an 18" raised spa 3'6" to 8'6" deep. The pool equipment is 51' from one skimmer and about 21' from the other skimmer. The plumbers used 2" PVC for 75% of the run and used 1.5" PVC on 25% of run (in last part of run to skimmer) for the skimmer furthest away from equipment. The closer skimmer has all 2" PVC.

I asked my pool builder what size PCV was used to skimmers and he said 2". When I asked him about the 1.5" PVC in the run to the skimmer he said it was done intentionally so that the skimmer furthest away from the equipment will have better suction and that of equal amount to the other skimmer closer to the equipment.

Does this sound right?

Many thanks!

 

[jblizzle]

Does not make sense to me. Going smaller would add suction loss and lower the flow rate. Water will take the path of least resistance.

It would be best to have them both run to the equipment pad with 2" and valves to adjust the suction.

 

[linen]

Welcome to tfp, DCFan9

Nope, I agree with jbliz, going smaller will only decrease the flow from that skimmer.

 

[jtech1]

I am no expert on this, and I may be missing something... but, it sounds like they ran out of 2" pipe. Ask him to explain how impeding the flow on the farthest skimmer (the one that already has more impedance due to the longer pipe run) will help even them out. To get equal flow you would want to impede the nearest skimmer which is the path of least resistance otherwise.

A valve on each skimmer would allow you to adjust flow to whatever you want.

 

[bmoreswim]

Maybe he was thinking like it was on the return side. I can picture the water lines in my house get smaller the farther away from the source they go (which I presume is to keep the pressure up?). Doesn't sound correct for this though.

 

[jblizzle]

Maybe he was thinking like it was on the return side. I can picture the water lines in my house get smaller the farther away from the source they go (which I presume is to keep the pressure up?). Doesn't sound correct for this though.

I don't think that is to keep pressure up, it can just be smaller and maintain adequate flow rate because it is supplying fewer fixtures. Likely a cost saving measure during construction.

 

[DCFan9]

Thanks for your responses jblizzle, Linen ,jtech1, bmoreswim ! After reading your responses I contacted the PB and he quickly offered to swap out the 1.5" PVC with the 2". He shared that he has great faith in his plumbers and was certain they did this for good reason (explanation in original question). None the less, they will be out this week to replace.

 

[jblizzle]

So will you have a valve to adjust the flow between the 2 skimmers? If not, you could put a float diverter in the nearest skimmer that will allow you to close of part of the from that skimmer to force more from the other one.

Is there a floor drain? How is that tied in?

 

[DCFan9]

Jblizzle - I am not sure if there is a valve to adjust the flow between the 2 skimmers - i think that would be a good thing to have, but will ask PB. Which is better: Float diverter or valve for skimmers?
Yes, there is a main floor drain connected via at least a 2" flex pipe but not sure how it is tied in - i will look in the a.m. its dark now...

Added some pics- maybe that will help?
MJ

 

[jblizzle]

Well, I see 4 suction lines in front of the pump, so that could be 2 skimmers, pool floor, and spa.
I see the pressure cleaner line. I am not sure what the pipe sticking up in the air with a valve and 2 pipes going into the ground is for.

Did no-one here yet suggest you to ditch the Nature 2 system? Certainly do not use the mineral portion of it as the added metals can cause expensive staining and green hair. Not to mention that they are expensive and a few have been known to break open and spray the metal all over the pool.

 

[DCFan9]

jblizzle - maybe the pipe pointed up is for the volcanic air (Polaris Metal Blower) which is for the spa?
Doh!- nature 2! i did see all of the warnings about the Nature 2 and to be honest since the equipment was just set last week, i did not know what this was until you pointed it out. Is this something i can just remove all together?

 

[jblizzle]

Odd that the blower has a valve with 2 outputs

Well, the Nature 2 Fusion Soft is a combination of the salt water chlorine generator (which I assume you want) and their mineral pack. If you completely remove it, you will not have a SWG anymore. I think there are some threads about how to run it without the actual minerals though (like cutting open the mineral pack and removing all the pellets or something).

 

[diyindux]

I actually ran 1 1/2 inch line to my skimmers and connected them to a 2 inch line to the filter via a tee. My skimmers have an adjustable plate on the outlet I can use to adjust the flow from each one. By keeping the velocity up in the lines I certainly don't need to worry about anything settling out!

My pump has a 2 inch inlet and is fed via a 3-way 1.5 / 2 inch Jandy valve. I'm certain the head loss there is greater than what is lost in the 1 1/2 inch line from the one skimmer. The pump is drawing from 2 skimmers and a bottom drain, so that one run shouldn't be a big problem. That being said, 2 inch lines certainly have the potential to flow more and definitely won't hurt things. And having every function controlled through valves at the equipment pad is super easy so get that if you can. I had most of the plumbing run based on guidance from the pool kit manufacturer before I became enlightened by this site so I'm running on 1 valve at the inlet and 2 on the outlet even though I have 2 skimmers, a bottom drain and 6 returns. Everything seemed to work just fine though so I guess I got lucky.