external pump without drilling hole?

[Minnreefer]

Can I use an external pump for a return pump without drilling a hole in my sump? I know that a hole would be the best but I can't easly remove my sump and drill a hole. I would do a U over the sump sides and keep the intake of the U close to the bottom of the sump.

Thanks

Jon

[mojoreef]

Yes Jon it can be doen. I believe you need what they call a prime resivior. It is an attachment to the external that will always hold enough water above the pump in order to prime it,


mike

[Casey]

Thats what I was thinking you need something to help prime it.

[Doug1]

Hmmmmmm I think Andy or someone has closed loops with the pump plumbed over rather than drilled, wouldn't it be the same thing more or less?

[Casey]

Would be the same Im just wondering how to keep it primed,wouldnt it lose it in power failure??

[Rick O]

Originally posted by Casey
Would be the same Im just wondering how to keep it primed,wouldnt it lose it in power failure??

It shouldn't. If the pump is sitting on the floor or lower than the water level in the sump then there should always be water in the pump and the pipe going to the pump. It would be a trick to prime it the first time but should work fine after that.

[Geoff]

i do not know the exact volume but i have heard twice the length/volume is enough to prime reliably. if the water in the sump is very high when the power goes out it is much easier. i would look and see what the equalibrium point in the sump is. you will need to keep the pump below the sump water line at all times.

there are ways to cheat, like the U coming out of the sump being 1/2" then expanding it 3/4" or 1" once it is below the sump water line could give you enough of a prime reservoir. just an idea.

i know check valves are fairly unreliable but maybe you could put one on the return. another idea could be to put a sprinkler valve on the return line. when power goes out then it shuts. this should essentially cause a closed loop.

G~

[Minnreefer]

Thanks everyone, I keep my sump water level fairly high so that should not be a problem.

Jon

[cyberchef]

You could also just use a "self" priming pump and not have to worry about it.

[Geoff]

Originally posted by cyberchef
You could also just use a "self" priming pump and not have to worry about it.

Now where is the fun in that.

i hate it when people find the obvious solutions.

G~

[David Grigor]

Jon, Clyde did exactly what your talking about.

I saw some pics of it in some old threads quite some time ago.......

Only trick is getting it primed the first time.

[schrader mo]

You can easyly get it primed by just getting a powerhead with a hose and shooting the water into the u tube.