Plumbing Question

[NeuroDoc]

Due to size constraints in my stand I find myself needing to put a bend in the pipes on the intake side of my return pump. My pump is an Blue Line HD40 3/4" in and out. Are there any big issues with putting a 90 degree bend on the intake side?

 

[shallowreef]

I don't think one 90 degree bend is going to cause that much trouble but i'm not a pro at this sort of subject.

 

[wrightme43]

Depending on where it is at, it could cause cavitation. Think blowing across a coke bottle and the wistle that follows. I think the rule is at least 2.5" away from the pump intake. It might be more. Could you use two 45 degree bends? If so that will help alot.

 

[NeuroDoc]

Thanks for the input. I had a breakthrough this morning when I realized I can just get a threaded union to attach directly to the pump. I had glued the union to a thread adapter which made it stick out too far. Unfortunately I am out the ~$5 for the slip union I already glued, but live and learn (and measure twice before I do anything else).

And another plumbing question. Can a threaded connector, of any type, be overtightened if threads are still visible on the male end? If I take pliers and tighten a threaded connection as tight as I can, is it possible to damage the connection if I don't screw past the end of the threads? I hope that made sense.

 

[VegasMike]

Yes, you can overtighten it. It may not cause any "real" damage to the fittings, but they will leak. It's best to wrap the threads with a few revolutions of teflon tape and hand tighten as tight as you can by hand.

Your other option if you still need to put a 90 degree bend on the intake is to upsize the plumbing on the intake side (or at least for the bend). I usually try to go one size up on the intake just to maximize the Pump performance and life. I don't go down to the actual inlet size until the last fitting before the pump.

 

[Krish]

And another plumbing question. Can a threaded connector, of any type, be overtightened if threads are still visible on the male end?

I over tightened a male connector on a pump of mine before with pliers and snapped the whole head off of the pump! Once you use the teflon tape like vegas Mike suggested, you only need to "snugly" tighten it by hand and you will be fine. As for the 90's, One thing I try to use in place of a hard pvc 90 (elbow) is some flex pvc so it can make a gradual smooth bend in the direction I want. Works like a charm

 

[NeuroDoc]

So I think I can change my plumbing to make room for a straight run into my pump (no turns), I'll have to check when I get home. However, I had shortened the outlet from my sump in trying to make room, and now I wonder if the distance from the sump to the pump might be too short. Is there a minimum distance that water should flow through pipes before it enters the pump?

 

[sryder]

you can always use hoses instead of hard pipe.

 

[Krish]

now I wonder if the distance from the sump to the pump might be too short. Is there a minimum distance that water should flow through pipes before it enters the pump?

Not at all...You can have the pump as close as you like. Don't forget some pumps sit is water and suck it in directly so you're good if I am understanding everything correctly

 

[NeuroDoc]

Thanks for all the help guys. Last question, I hope. I am installing unions in a few places. They are not labelled in any way. Is there a particular direction that water should flow through, male to female or vice versa? I really don't think it matters, but I figured I would ask before gluing this time.

 

[Scooterman]

Glue away water will flow through these easily enough either way, also in most cases A 90 right out the suction of a pump is no biggie also.