Opinions on pipe sizing

[Cod3Monk3y]

I'm currently planning out the plumbing for my pool and wanted to get some opinions. Some details:

• 13,000 gal.
• planning for a variable speed pump
• 2" plumbing on equipment pad
• 2 skimmers; each with home run to the pad
• 6 returns; paired for 3 runs to the pad
• 1 return for possible future water feature

My first inclination was to run 2.5" pipe for everything to/from the pad, but I'm wondering if that's overkill for my setup.

I'd love to hear some opinions.

 

[mas985]

If you are already running home runs then 2.5" is probably overkill. 2x2" lines have less head loss than a single 2.5" line so you already have effectively "large" pipe.

As for the return, you could do the same and run 2 sets of 3 returns off separate lines but that may not buy you much. What is the distance from the pool to the pump?

 

[Cod3Monk3y]

The pool will be about 40' from the pad. I was still thinking of going 3 sets of 2 returns just to allow me a bit more control over return pressure at various areas of the pool to help me dial it in best.

Thanx for the feedback. I had actually read the head loss comparison before, but had completely forgotten it during all my research.

 

[mas985]

You have to be a little careful. You don't want the return head loss to be less than the suction side or it will cause some pump issues. However, if you have valves on each line you can always add head loss if necessary.

 

[Cod3Monk3y]

Ah, I had not considered that. I do plan on having valves on each line so I should be able to accommodate the adjustment at the pad. Without running numbers on all the lines to compute head loss, is there a general rule-of-thumb way to determine how much to close return valves to help equalize that?

 

[mas985]

Yes you can compensate with the valves on the pad but that does tend to make noise at higher flow rates. Also, running on lower speeds is less of an issue anyway so for normal circulation at low RPM, it may not be an issue at all.

But generally, if you keep the suction side pipes larger than return side and/or the number of suction pipes higher than the number of return pipes, there is almost never an issue. Also, any other equipment on the equipment pad can help with the offset such as filters with multi-port valves or heaters both of which have fairly high head loss.

 

[Cod3Monk3y]

OK Great. I plan on having a filter, heater, and SWCG as well. I appreciate the input.

 

[mas985]

What kind of filter? Cartridges have very low head loss.

 

[Cod3Monk3y]

Current plan is a Pentair cartridge CCP 520, Pentair 400k heater, and Pentair IC40.

 

[mas985]

So those are all pretty low on head loss but there is a good chance you won't have any issues.

 

[JamesW]

Current plan is a Pentair cartridge CCP 520, Pentair 400k heater, and Pentair IC40.

The heater requires 40 gpm.

That should be the highest flow rate that you will need unless you plan to have some sort of water feature.

I would suggest the IntelliCenter to control everything.

The IntelliCenter can increase the speed of an Intelliflo pump on call for heat.

When not heating, you can probably run at about 20 gpm continuously and get good results with very low power costs.

Will the system be the same elevation as the pool or higher or lower?

 

[Cod3Monk3y]

OK. Good to know about the heater flow rate. Yes, the pad will be at the same elevation as the pool. I've been debating on the IntelliCenter, but I'm a bit leery on jumping in. I'm sure once I got it hooked up and configured I would like it, but I don't want to get too far in over my head since I'm doing most of the installation.