1. ## pipe size

I see pools using 2" and some using 1.5" runs to and from the pool to the pump.

Is there a standard or formula which to use?

2. ## Re: pipe size

It depends on the water flow rates and pipe length. For most in-ground pools, I would advise against 1.5 inch pipe.

3. ## Re: pipe size

Well the pump will be located 30' from the pool it is about 5700 gallons,

If the pool is not supposed to turn more than once in 6 hours or in this case 1,000 gal an hour I thought 1.5 might be big enough.

How do I calculate the correct pipe size?

125gpm on 2"

4. ## Re: pipe size

Originally Posted by Nova13
125gpm on 2"
From Hydraulics 101...to keep the flow rate below 6 ft/sec, 1.5" pipe should have a maximum of 38 gpm and 2" pipe should have a maximum of 63 gpm.
Originally Posted by Nova13
If the pool is not supposed to turn more than once in 6 hours or in this case 1,000 gal an hour I thought 1.5 might be big enough.
Is this a nsp requirement? I think you will have a hard time moving water at that low flow rate with conventional pool pumps...a variable speed might work...though they are pricey.

5. ## Re: pipe size

I have a 1.5hp single speed I want to use, but about 30-35gpm will be diverted to solar.

The balance to the pool, don't care about the pipe cost difference just want what will work best.

based on those flow rates I need 2" it sounds like

6. ## Re: pipe size

Looking at those pump flow rates maybe I should just sell the 1.5HP,

Since it's kinda a small pool maybe a 3/4HP to do the pool and a 1/2hp for solar.

I need about 30-35gpm for solar on a story roof 7 panels @ 4gpm each plus the loos of plumbing

7. ## Re: pipe size

Is your solar a separate loop from pool? Most of the people I have read about use the same pump for both solar and pool. Also I am petty unclear but my impression is that you don't lose flow rate in a simple linear number per panel... You have a certain amount of head that gets added by your solar which impacts overall flow rates.

Might be good to look into 2 speed pumps also.

Sent via Tapatalk...

8. ## Re: pipe size

I think the two pump idea won't work, I'm going to look at selling 1.5hp jacuzzi and sizing out a new 3/4hp pump maybe a 1/2hp

9. ## Re: pipe size

I use a 1hp 2 speed with my solar. I run on high when I divert to the solar and low when I do not want solar ... like in the winter. A 2 speed would be a cheaper route than having 2 pumps both initially and fit electricity.

As far as pipe size, bigger is better as you will have lower head loss and thus higher flow rates.

Posted from my Droid with Tapatalk ... sorry if my response is short

10. ## Re: pipe size

Spoke to tech support at lifeguard,

He said to go 2"

Also recommended a R175316 ½ HP SeaFlow 230V I found one at \$485.

Any place I should try for a better price?

11. ## Re: pipe size

You will be much better off with a two speed pump, which can be found around/below that price.

12. ## Re: pipe size

I agree with JL.

Originally Posted by Nova13
Also recommended a R175316 ½ HP SeaFlow 230V I found one at \$485.
That looks like it is likely a Pentair superflo model: SF-NI-1/2FE. If it is, it is overpiced compared to other online sources, one of which is: http://www.poolsupplyworld.com/super...htm?a=%20R|102.

I too would probably still go for a two speed, and run on low most of the time for the nsp. Maybe something like the Pentair superflo 2-speed 341111 (SF-N2-3/4A), see: http://pentairpool.com/pool-owner/pr...-pumps-165.htm. Might be had for less than \$500.

13. ## Re: pipe size

Well what 1/2HP pump is 220V with 2" in/out in two speed about 30/60 gpm.

Under say \$500

14. ## Re: pipe size

Originally Posted by Nova13
Well what 1/2HP pump is 220V with 2" in/out in two speed about 30/60 gpm.

Under say \$500
The one I pointed you to above includes 2" external slip fitting unions. One place from googling is \$450 shipped:http://www.swimmingpoolsetc.com/pent...ndpoolpump.htm (I have not bought from this store). I would guess it is available other places too.

15. ## Re: pipe size

I see that but the specs are
Voltage: 115

I was trying to find 220v at about 6amps max

16. ## Re: pipe size

You want the 1 HP Superflo 2 speed. SF-N2-1A - 230v

It will produce about 70 GPM on high and 35 GPM on low for typical 2" plumbing.

17. ## Re: pipe size

oops sorry about missing that...mas has got you covered

18. ## Re: pipe size

Originally Posted by mas985
You want the 1 HP Superflo 2 speed. SF-N2-1A - 230v

It will produce about 70 GPM on high and 35 GPM on low for typical 2" plumbing.
Yup. That is what I said too

19. ## Re: pipe size

I looked at the flow curves, looks like it will work fine with a bit of reserve gpm.

Now trying to shop it for best price.

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