Priming external pumps

[Rosco's Reefs]

I purchased an external pump for a water movement system I am designing and after pulling out my hair (and I'm bald already) I called Tech Support. They guy there told me this particular pump (a panworld from BRS) required priming before it would pump...

 

After I fussed about lack of documentation, etc. etc., he said just about all external pumps are this way...

 

Is this true?

 

As with many of my grand designs, if true, it will be back to the drawing board.

 

Did I say in an earlier post that the DIY was my favorite part of the hobby? I take it back!

 

Thx WAMAS!

 

 

[Jon Lazar]

Most hobby level pumps are centrifugal, which can't pull enough air through to self prime. We get around this by normally mounting the pump low enough that the water from the sump fills the pump, even when it's off.

[Coral Hind]

Can you detail the situation so we can maybe offer a fix?

[Guest thefishman65]

i agree details there should be a fix. Maybe the first time it needs to be primed, but after that if you leave it with some water you should be ok.

[jtro]

To prime mine at first I had to back fill some water down the output line .Then when I felt it was enough it started up perfectly !

[Origami]

Most hobby level pumps are centrifugal, which can't pull enough air through to self prime. We get around this by normally mounting the pump low enough that the water from the sump fills the pump, even when it's off.

+1

 

If you provide a drawing of your setup, maybe we could give more help. In any case, you need to get the air out of the intake side of the pump to give the impeller something to "bite" on. You can do this by pumping water up into the intake, or by drawing air out of the intake. Either way should work, but you need to get the air out.

[Rosco's Reefs]

Thx all. I will draw it up, write it up and post it.