Question about slowing down return flow. (1 Viewer)

[Guest]

Ok, I have my return pump setup externally, and a ball valve in between the pump and my sump so that I can shut off water flow when I'm changing out the pump.

Can I adjust the flow with the ball valve before the pump?
Or will that make the pump work too hard?
Does it make a difference in the stress put on the pump if the ball valve is before the pump inlet or after the pump outlet?

Thanks,
BTW, I'm still DESPERATE for a different external return pump.

 

[Guest]

FMB,

Try this. Why not put a vertical T in your return, with one line going back to your sump. On the line going to your sump, put a ball valve which you can open or close to regulate the flow of water returning to your display tank. This puts virtually no back-pressure on your return pump.

Here's a quick and dirty diagram:

 

[Guest]

If your going to use a valve to reduce flow, put it after the pump, not before. Putting it before the pump will shorten the life span of it.

 

[Guest]

Bill,
I am a valve sales engineer and get asked this question regularly.
First: you can use a ball valve to restict out put, with no adverse affect, as long as the valve is not closed more than 75%. Beyond that point, with CLEAN media, the valve will not suffer any damage. The important point being CLEAN. If you suspect ANY suspended particle in the system then you can expect erosion of the ball to occur.
If you want to discuss further, PM me and we can talk.
Chuck

 

[Guest]

I think he's more worried about the effect on the pump rather than on the valve.

 

[Guest]

OK. The simple answer is that any configuration may or may not cause premature wear on parts depending on the configuration.
The bottom line is this, if you hear noise in the system which you think is coming from "cavitation" then you'll have problems.
PM Me if you need details.

 

[rhane71]

Ok, here it is plain and simple. If you close the valve before the inlet of the pump you will cause cavitation and ruin your pump by burning it up. You want to control your flow on the discharge side of the pump. Most pumps are made to handle back pressure but not all. Now I assume you are using a PVC line and valve. This being assumed, your PVC valve is most likely a ball valve. These are regualrly used for fully open or fully closed service. You can use them for flow control but fine tuning is very hard. If you want a finer control of your flow I would use a gate valve. This will have a wheel that you turn to open or close. They are a few dollars more but better for finer flow control. They are also harder to find. You may have to go to a plumbing supply to buy one. The DYI stores like Lowes and Home Depot in my area stopped carrying them about a year ago. I personally use a block valve before and after my pumps so that I may take it out of service for preventive maintance or repairs. Here is kinda what I have on my tank. this set up makes my life so much easier when I need to work on my tank or work on my pump.

 

[rhane71]

By the way that box is my sump with the return pump...