Reducing flow of waterfall.

slicerd · Apr 5, 2012

Hi guys I am new to pool ownership I have learned a lot from this forum and pool school but still have a few questions.

I have a waterfall powered by its own pump and it really pushes a lot of water and makes a nice looking feature. But I would like to turn down the water flow sometimes to create quieter more relaxing mood. Right before the pump is a 2 way Jandy valve I have partially closed the valve and it reduces the water flow to the pump but I am slightly worried that reducing the water flow to the pump while its running might cause issues in the pump or the pipes.

I am at work right now and don't have stats on exact pipe/pump size and valve type but if needed I can get the info and maybe some pics tonight.

Thanks

JasonLion · Apr 5, 2012

That is a very reasonable way to reduce the flow rate. You can usually tell how the pump is doing by the noise it is making. As you turn the valve the noise should stay more or less the same for a while and then start to get louder quickly. As long as you stay away from the louder quickly area you should be fine.

The will only way to damage the pump would be to turn the water flow off nearly completely. That would cause the wet end of the pump to overheat and possibly melt.

jblizzle · Apr 5, 2012

Well, Jason beat me ... here are my comments

:wave:

Welcome

Given your description, it sounds like the only control you have to to reduce the suction by closing the valve. I assume it is wishful thinking that there is not another 3-way valve on the return pipe to the waterfall with bypass route back to the pool?

It would certainly not be good to completely close the suction valve and you will run into overheating issues. In my mind as long as you are getting some water to the pump, I think it should be ok.

Certainly not the most efficient way to reduce the flow as would be possible with a variable speed pump.

There are a few options like maybe connecting the waterfall to your main pump and not using the separate pump; getting a smaller waterfall pump; adding a bypass line (not likely very easy) ... but these kind of depend on your setup and desires.

Highlandreef · Apr 5, 2012

Beat me to it so what they said

slicerd · Apr 5, 2012

Thanks for all the responses guys. I will turn on the waterfall tonight and listen as I reduce the flow. Maybe if/when the pump dies I will look into a variable speed pump.

mas985 · Apr 5, 2012

The pump should actually get quieter has you restrict more flow because the flow rate is reduced through the pump. This also reduces the load and power consumption of the pump so there is really no danger to the pump motor unless you shut off the flow completely. However, the throttling valve may get louder because of the restriction as the water velocity increases through the smaller orifice of the valve.

jkapp · Apr 5, 2012

Does it make a difference to any of the answers above if the two way valve is on the suction side or pressure side of the pump? I have a similar issue with my sheer decents, but only have a two way valve on the pressure side.

Thanks!
John

mas985 · Apr 5, 2012

It can make a big difference. You should only restrict the return side a pump for the type of flow rate reduction that you are trying to accomplish. Excess restriction on the suction side can lead to cavitation so it should be avoided. However, you can redirect flow on the suction side for a cleaner or to create more suction for a skimmer but even that has its limits.