Help me understand this underground plumbing setup?

brian113 · May 20, 2020

I'm prepping to hook up plumbing for my new heat pump this weekend, and as I dug out the space around my pipes, I was a little surprised by what I found.

Background: The pool was installed before I bought the house. I never really understood the purpose of the 3-way valve's placement, but as long as the system worked, I didn't worry about it. The Pool Frog hardware predates me; I've never used it to disperse chemicals.

Anyway, with the installation of the pool heater, I was planning on ripping out the Pool Frog, installing a bypass system and having one pipe carry the water back to the pool. But when I excavated some of the dirt, I was puzzled by what I saw — three pipes leading away from the the cement pad to the cement pond. I assume they connect somewhere underground, but I haven't reached that point yet.

Before I dig more to tear this out, I'd like to understand why it might have been installed this way. After all, I could simply alter my plans to tie the updated above-ground system into that 3-way valve and not worry about what's happening underground if it's not necessary.

Any thoughts why this was configured like this?

ajw22 · May 20, 2020

How many returns do you have in the pool? No spa? Pressure cleaner?

brian113 · May 20, 2020

One return. No spa. Just the pool.

I Wondered for a second if there had been a spa previously, but thanks to the historical images on Google Earth, I know when the pool went in and there never was any other water feature.

ajw22 · May 20, 2020

One return is surprising. Even a pool with one skimmer usually has at least two returns.

And it is interesting that one pipe is flex PVC and two pipes look like rigid PVC underground.

Jimrahbe · May 20, 2020

Brian,

It is pretty clear to me that at one time you had three places for the water to get back to the pool.

It could be..

3 eyeball returns... Maybe two were capped off and a new liner installed over them??

Maybe they repurposed the main drain into a bottom return. ???

An abandoned water feature???

If it were my pool I'd sure want to know...

Thanks,

Jim R.

brian113 · May 21, 2020

Now that the sun's up, I took a look again and feel a little sheepish that I didn't connect the dots, but there are a couple of of plugs in the pool — one along the wall in the deep end (across from the lone skimmer) and one on the steps. After I bought the house years ago, I wondered about those for a couple of days but couldn't figure them out, so I just forgot about them. Would those be typical locations for eyeball returns? (Actually there's a third plug, too, right around the corner from the plug I circled on the steps.)

(If that's the case, I also assume the flex PVC is the line that would led to the plug on the other side of the skimmer, since that return would have the longest, curviest route to get to the filter.)

Anyway, if that's what those pipes are for, the question is then: Do I mess with those three lines or simply connect the above-ground plumbing into that three-way valve?

I assume the answer is just connect to the valve — why tear out infrastructure I might take advantage of in the future, right? Maybe when I replace the liner in a year or two, I'll want to reactivate those returns.

ajw22 · May 21, 2020

Two possibilities...

First, two return lines had leaks and were taken out of service.

Or, someone never removed the plugs when opening the pool one season.

I would unscrew the plugs and see if the returns work and don’t leak.

How long have you been in the house?

brian113 · May 21, 2020

I've been here ten years.

Jimrahbe · May 21, 2020

Brian,

If the lines were leaking they'd still be leaking as you have the Jandy valve sending water down the lines right now...

I suggest that you take the plugs out and see if you have water coming out.. If you do, then add eyeballs, and be happy that you have more than one return.

Thanks,,

Jim R.