Multiport making weird sound

[Henjohnny]

Recently bought new home with pool. The multiport valve should have been replaced as it was part of the request repairs; however I am no confident it was really “repaired”. When I run the pump in filter, the multiport valve makes a gargling sound (like there’s something stuck in there or like small rock kicking around). This sound is not permanent and comes and goes frequently. If I run the valve in anything else (backwash, filter, recirc) I do not hear any sounds. Any suggestions as to what it could be?

16 by 32 ig vinyl pool. Hayward DE3600 filter. Hayward 1.5HP super pump

 

[jblizzle]

Welcome to TFP!

Why not open it up and take a look? Just have to remove the 8 nuts and bolts.

 

[JohnT]

Are there bubbles or turbulence in the pump strainer basket?

 

[JamesW]

This can happen when the flow through the multiport is too fast, especially if the water has air bubbles or dissolved gasses.

A 1.5" multiport has a faster water flow than a 2" multiport.

I suspect that the noise might be where water goes past a sharp edge and creates low pressure vortices. Possibly a type of cavitation.

The pump is really too big, especially if the multiport is 1.5".

 

[Demegrad9]

If you choose to open it up just make sure to only hand tighten the 8 screws/nuts back together. The Hayward multi port valves are pretty much all plastic and if you crack it, it's pretty much done.

 

[Henjohnny]

Are there bubbles or turbulence in the pump strainer basket?

Nope, runs smoothly which is why I ruled out a potential air leak

 

[Henjohnny]

Welcome to TFP!

Why not open it up and take a look? Just have to remove the 8 nuts and bolts.

that was the next step, but figured I’d ask before diving into it.

Thanks for your help!

 

[Henjohnny]

This can happen when the flow through the multiport is too fast, especially if the water has air bubbles or dissolved gasses.

A 1.5" multiport has a faster water flow than a 2" multiport.

I suspect that the noise might be where water goes past a sharp edge and creates low pressure vortices. Possibly a type of cavitation.

The pump is really too big, especially if the multiport is 1.5".

After a lot of research (thanks to this forum!!) this is what I suspected as well. Going to do the calculations to confirm it once I finish troubleshooting all the problems with the pool. It’s definitely a 1.5” multiport valve.

Wouldnt I get the same water moving too fast in other settings (recirc) too? That’s the only thing that throws me off

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If you choose to open it up just make sure to only hand tighten the 8 screws/nuts back together. The Hayward multi port valves are pretty much all plastic and if you crack it, it's pretty much done.

Will do. Thanks for the heads up. I’ve replaced enough parts for this summer :grin::grin::grin: