Schedule 80?

[josephny]

I'm still planning my pool and I'm undecided regarding the piping.

I'm in central NY, where the Winters can have weeks in the single digit temperatures and the soil has tremendous numbers of rocks of all shapes and sizes.

I like the idea of flex PVC for it's ease and reduced water flow resistance, but I'm concerned about insects/animals/abrasion damage.

I was thinking about using schedule 80 PVC instead of 40 because of its added strength.

Does anyone use schedule 80?

The pool I'm working on is 22x44 by 9' deep at it's deepest, so I was thinking either 2.5" or 3" for the sched 80.

Does this make sense?

Anyone have a good source for quality PVC at a reasonable price?

Thank you!

 

[JVTrain]

Schedule 80 is likely overkill and will only increase your expense without much benefit. Both are roughly equal in abrasion and strength but the 80 allows higher pressures. Pressures that should never be present in pool plumbing. I would certainly recommend rigid schedule 40 over flexible PVC. It's more labor cost, but in the end, it's the same or less to do rigid PVC and rigid PVC is not as vulnerable to insect or abrasion damage.

As far as diameter goes, the larger the diameter you have, the less head loss you have for more efficient flow and pump usage. 2" is recommended, 2.5" would be even better. 3" ... again, might be overkill and increase cost quite a bit and not necessary unless you're going to have a spa with lots of jets. Check out Hydraulics 101 - Have you lost your head?

 

[JoyfulNoise]

The way to protect pipes from abrasion and thermal cycling is to make sure your pipe trenches are below the frost line in your area. As well, when the pipes are assembled and final pressure testing is complete, the trenches should first be backfilled with sand (decomposed granite) immediately around and above the pipes and then finished off with native soil backfill and compaction.

I would also chose rigid SCH40 PVC over flexible.

 

[josephny]

Thank you both!

Schedule 40 it is.

2.5" seems like a good choice.

Sweep 90s instead of regular?

Now I need to make a final decision on drains, returns, skimmers, etc.

I'm leaning towards not having main drains, and using 3 skimmers instead of Aqua Genies, and a dedicated return for a cleaner/vacuum.

I've been looking for diagrams to help me understand better, but can't find a "no main drain" diagram.

Thoughts?

Thanks!

 

[xyz]

Sweeps, if you can find sched40, are far less flow friction than elbows. With 2.5, may not matter given low flow velocity. Sweeps can't hurt.

I have a deep ish pool, and did not get good circulation (warm water on top, cold down deep), until my main drain was fixed.

 

[atttech-2]

When they did my pool they heated and gently bent the schedule 40 to conform to the contours of the pool. There were very few 90's used and no 45's, most of the 90's are at the equipment pad and of course the T's where the returns split off.
One somewhat unique thing they did was install 2 returns called DP's in the floor of the pool these are on their own valve and will be the dedicated return for solar heat when I get it installed. The theory is returning the heat to the bottom of the pool gives more uniform heating and you can install with fewer control and check valves so operation is a bit less complicated.
If you do go the no main drain method, I would install equalizer ports below the skimmers. If they ever get blocked with debris it will keep the pump from starving for supply water.

 

[Veccster]

Are you installing a vinyl pool?

I did NOT want any floor drains in my vinyl. It's a point of failure for many and impossible to fix (you just end up plugging it if it leaks). At least wall returns and skims can be accessed by digging behind them.

I have a wall return in the center of the deep end that I plan to point down. You could plan on using something like the Venturi return valve to push water deeper into deep end and aid in circulation. Infusion Pool Products - Save Time, Energy and Money with our new, easy to install Venturi Return Fitting.

When planning your layout, keep wind in mind - try to have your skims downwind.

 

[xyz]

Good on you for the 2" solar return. That is ideal. I wish I had one. Also, returning warm solar water to the bottom would help avoid the stratified layers like I had before my bottom feed was fixed.

So id also suggest you double up on 2" and avoid 2.5. I had trouble finding fittings for 2.5' and the cost jumps. 3" is often cheaper, probably because it is more prevalent. May be different in your area.

Said I'd another way, let's look at a scenario, say for 4 returns. You could sent 1 2'5" return to your pool, tap off the eyeballs, and get good flow with low flow velocity. Or, you could use 2 2" returns each with 2 eyeballs and get more efficiency (lower velocity) by a factor of 6.3/5 or 1.28 or 28% improvement. Since here 2.5 is nearly 2x the cost of 2, this is better flow and cheaper. Also, 2" sched 40 sweeps are available, so the
at helps efficiency too.

Basically, what I'm saying is, I think if you stick with 2", use sweeps where you can, and just double up in high volume areas till you get to the pad, it will already be overkill unless you are going for a 50,000 gal or larger pool. And then I might still recommend 2", just get 2 of everything.

Also, at the pad, are you going to get 3" valves? Will you be using commercial pumps that have 3" connections? Will you have 2 high flow filters in parallel?