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BigSplash
06-02-2006, 07:45 PM
I would like to add in a solar heater, however doing this I will need to add 140' (total) off 1.5" pvc pipe plus 8' vertical rise.

I need to maintain a flowrate of 25 gpm since my SWG requires this pressure.
I have a 3/4 hp Hayward superpump, specs say that with 50 ft of head I can maintain a flow rate of 31 gpm.

I am trying to calculate the "head loss" of my total system, so far I have come up with:

Hayward Sandfilter = 15 ft
140' 1.5' pvc = 6 ft
Solar panels = ? ft
8' rise 1.5" pvc = ? ft
10 elbows = 2ft
Scimmer & drain = 0.2ft

So it seems I am still way under 50 ft of head loss.
Does anyone know the headloss for the 8ft rise?

Anyone see any problem with my calculations? :D :D :D


Calculator for Head Loss
http://www.freecalc.com/fricfram.htm

duraleigh
06-02-2006, 07:57 PM
Aside from the friction of the pipe, the rise is irrelevant.

The water is "pulled" by gravity on the down side equally as much as your pump had to "resist" gravity pushing it up the rise.

mas985
06-02-2006, 08:33 PM
Bigsplash,

You will get a more accurate head calc using the PSI from your filter. If you also have a vacuum guage (easily bought at Sears), you can also get the suction head too.

Total Head = Filter PSI * 2.31 + Pump Vacuum (in. mg.) * 1.13

Use 8 in. mg. if you do not have a vacuum gauge as a good guess.

Solar panels are difficult to determine the head because there are too many factors. However, a worst case would be an additional 10 PSI on you filter pressure.