Crack in Hayward Super pump housing wth pics

[Daggit]

Thanks Poconos. My real concern is the length of the plumbing (feet of head) as I have not been able to find how to definitely calculate this. For example I don't know if I should count the return line in the total feet of plumbing, since it is after the pump. If I only count the skimmer to the pump the plumbing may be as little as 36-40 feet, but if I cant the return line as well then it could be as much as 90 feet of plumbing!

Once I know if I can use just the skim line or if I need to use both then I can see what size pump I will really need.

I am stuck between the 1HP and the 1.5HP. The 1HP is rated 39GPM at 50 ft head, and the 1.5HP is rated 53GPM at 50 feet. These are both pretty close to the 1.5inch pipe max of 44GPM per minute, and well below the 80GPM max of the EC-75 filter. I guess I am just worried about breaking the pipes if the pump is too strong.

The feet of head that the pump develops is a differential between the suction and discharge. So, to figure this you need to figure the total elevation change between the pool level and the pump suction (a static head) plus the piping pressure drop in the skimmer line (the dynamic head) and then add that to the same calculation on the discharge side (static elevation change plus dynamic drop through pipe and equipment).

But...don't confuse feet of piping with feed of head. The expected pressure drop through 100 feet of 1.5" piping at 45 gpm is 5.85 psig or 13.5 feet of head. The other equipment in the system will overshadow this.

In practice, the suction-side elevation change and the dynamic drop through equipment on the discharge side have the biggest effect.

I wouldn't worry about breaking the piping unless you know of some reason that it was poorly assembled. Even a conservative pressure rating for the piping of 75 psig equates to 173 feet of head.

[bobjersey]

I emailed Hayward my pool specs and they told me that I should purchase the 1.5HP model (SP2610X15), so that decides it I'm definitely going with the 1.5. Thanks SO MUCH to everyone who helped out here, have a great summer!

[PoolDoc]

Ah, well. I am fixing photo links to make them permanent (so these threads are still useful in 2013 and after), and saw this thread again.