COR-20 Noise level

[allen00se]

COR-20 noise!!
Just plumbed my new tank and fired up the return pump for the first time only to be disappointed by the noise coming from it. Anything over 20% power level and I get a very loud hum. I hear others say their pump is not even audible so I am hoping there is something I can do to quiet this thing down.
There is no noticeable vibration if I put my hand on the pipe or pump, and I can even lift it off the sump bottom a little without any change to the noise.
Also there is no cavitation in front of the intake.
I have it plumbed with the 1-1/4” union to a 1” reducer all hard pvc to the tank.

Here’s a video though there is some background noise you can still here where I turn the pump up from 20% to 80%, it almost sounds like a vacuum cleaner.

 

[markwayts]

The video won't load for me but you need a chunk of flexible silicon hose between your pump and hard pipe.

 

[allen00se]

Trying again to post video

 

[allen00se]

The video won't load for me but you need a chunk of flexible silicon hose between your pump and hard pipe.

I thought about this but had seen others suggest that it was unnecessary and would restrict flow.

 

[markwayts]

It's only got to be a few inches. I think i bought mine from BRS.

 

[colossal_tater]

I would take it apart and reassemble and make sure everything is tight. I have mine hard plumbed and it is still quiet. It does have a bit of a whine to it, but nothing like your video. I only hear the whine because I worked to achieve total silence for my system. The whine is not noticeable unless I get my ear close to it and know what I’m listening for lol. I’m just crazy.

one last thing. I run at 55%, but whatever percentage the noise level really doesn’t change.

 

[allen00se]

I would take it apart and reassemble and make sure everything is tight. I have mine hard plumbed and it is still quiet. It does have a bit of a whine to it, but nothing like your video. I only hear the whine because I worked to achieve total silence for my system. The whine is not noticeable unless I get my ear close to it and know what I’m listening for lol. I’m just crazy.

one last thing. I run at 55%, but whatever percentage the noise level really doesn’t change.

What does your return plumbing consist of?

currently I use a reducer immediately to go from 1-1/4” to 1” then I have a union into two 90 elbows and 1 90 sweep into another union where it goes into the tank. I think that might be too much going on, so my plan is to go 1-1/4” pump - 1-1/4” sweeps to 1-1/4 x 1 - to the single union.

That would get rid of the elbows and one of the unions and keep the larger diameter pipe for longer.

 

[allen00se]

Just swapped out my pipes for mainly 1-1/4”, added a rubber boot connector, got rid of one of the unions and also all elbows. Sound seems a little better but still very noticeable, so now I guess I’ll break the pump down and see if there’s anything obviously wrong with it, not sure what else to do.

 

[allen00se]

Just for closure to this thread I will say that I took the pump apart and cleaned it even though it was brand new, once I reassembled it and added it back to the tank it was noticeably quieter, but still louder than I would expect. In a last ditch attempt to remove head pressure, I swapped out my dual 1/2" locline plumbing for the return in the display tank with some 3/4" locline... not only did it remove the remaining noise from my pump, but I would estimate that it increased my overall flow by 30%. In my mind since there was a 1" tee into the two 1/2" loclines, I didn't imagine it would create any back pressure, but I was obviously wrong.