Older Pentair Whisperflow making loud scream

[Jfair9]

I have the below pool pump that has recently developed a really loud buzzing sound while running. I've checked to make sure there are no obstructions, water is coming out of the returns in the pool, and I've backwashed the sand filter. I see no visible leaks. I'm able to manually turn the impeller without issue.

One thing to note is that if I turn my plumbing dial to 100% skimmer then the noise significantly reduces.

 

[ajw22]

Show us pictures of your equipment pad.

When your plumbing dial is not 100% where is it feeding water from?

You check the water level in your skimmers and that no weir doors are stuck?

You have an IFCS?

 

[Jfair9]

Not sure how to answer your questions sorry.

Here is a pic of the pad. Ignore the arrow.

 

[ajw22]

The red circled valve what you all your "plumbing dial"?

Where do the blue and green dot pipes go to?

 

[Jfair9]

Blue dot is skimmer and suction line.
Green dot is drain.

 

[ajw22]

You need to get your ear close to the pipes or pump and try and pinpoint where the buzzing is coming from.

Holding a big screwdriver on different places and putting your ear to the handle is often a way to see where it is the loudest.

 

[Jfair9]

What would I be trying to understand by listening?

 

[wireform]

Is the pressure on the gauge still in the same place it always was after backwash and is the return flow strong as it used to be. Perhaps a bad run capacitor and moving the suction side valve is just changing the strain on the motor a little so that's possibly causing a noise change too.