return pump question

[roundman]

I am putting a sump in the basement. Is there a problem with putting the return pump under the sump with 2 90 degree elbows or does it need to be a straight line out of the sump to the pump ?

Thanks

 

[mojo]

What Charlie said.

You can also oversize the pipe to reduce friction. For example, if your return pump uses 3/4" intake, then moving up to 1.5" for the intake plumbing will certain be enough to alleviate any additional resistance. If your pump is 1.5", use 2" pipe.

 

[roundman]

Thanks, that is what I figured, It would just fit better under but I can do it the right way.

 

[jonathan]

Don't forget the check valve!

Jonathan

 

[ichthyoid]

dawgdude;405319 wrote: You CAN however I would advise against it. Any elbows or turns will restrict the flow and cause more resistance. This can obviously be overcome with a strong pressure rated pump but its just better to be straight out from the pump to the tank. There was one website where you could select the pump, rise, run and number of 90 deg and it would give you the gph out. Ill see if I can find it.

Every elbow included in your plumbing will reduce the 'straight' flow approximately 6%, due to induced turbulence and 'boundary layer' (essentially friction) issues. So, for 2 elbows in a low flowing water system you will end up with approximately the following ...

100% x 0.94 x 0.94 = 88.36%, less any head pressure loss (loss due to height).

In a very high flow (highly turbulent) system things get worse. I doubt that you have a pump capable of producing those kind of flows, so go with the above. If you are interested in reading more about turbulence the following Wicki article is pretty good, but eventually gets very technical.

 

[schwaggs]

+1 on going with larger pipe. Using larger pipe reduces the speed at which the water flows, reducing friction.

Also consider using 45 degree elbow instead of 90s. Using 2 45s instead of 2 90s will almost cut the friction in half. You could also use Spa flex to reduce back pressure. The best solution really depends on your situation...

 

[rbredding]

BETTER YET....

plumb it out of FLEXIBLE SPA HOSE (it will glue into standard PVC 40sch fittings) it will not increase the pressure or cause any turbulence in the intake water... (but it couldn't be plumbed as tight as two 90's... )

SPA HOSE ROCKS for those "no fitting fits" situations...

 

[ichthyoid]

Schwaggs;405574 wrote: +1 on going with larger pipe. Using larger pipe reduces the speed at which the water flows, reducing friction.

Also consider using 45 degree elbow instead of 90s. Using 2 45s instead of 2 90s will almost cut the friction in half. You could also use Spa flex to reduce back pressure. The best solution really depends on your situation...

Very well said!

 

[jmaneyapanda]

Schwaggs;405574 wrote: +1 on going with larger pipe. Using larger pipe reduces the speed at which the water flows, reducing friction.

Also consider using 45 degree elbow instead of 90s. Using 2 45s instead of 2 90s will almost cut the friction in half. You could also use Spa flex to reduce back pressure. The best solution really depends on your situation...

Or, a sweep (if the plumbing is big enough).

 

[jason sartain]

Schwaggs;405574 wrote: +1 on going with larger pipe. Using larger pipe reduces the speed at which the water flows, reducing friction.

Also consider using 45 degree elbow instead of 90s. Using 2 45s instead of 2 90s will almost cut the friction in half. You could also use Spa flex to reduce back pressure. The best solution really depends on your situation...

You can also get more water volume,I changed my pipe from 1" to 2" and the water in my overflows went up 3" with the same return pump.