Sump Pump Check Valve Vibrates

Hello, quick question for the experts out there. I live in the
midwest and have a sump pump in the basement. PVC from sump pump runs
up the basement wall and across a 10 foot ceiling section and connects
directly to the city sewer system underground (I think).

Our sump had been making a BANGING noise at the end of each cycle.
Reading up about that, I determined it must be a bad check valve.
Replaced that myself. Still a lot of vibration. Had a plumber come
out...he recommended a new sump pump as our home is 12-years old.
Plumber installed that, and told me to secure the ceiling PVC better
to remove vibration. Winter came and I forgot about it. ;(


Now that we've had some thaws, vibration came back worse than ever. I
got some hangers and secured the PVC as solid as possible. Now, the
vibration is localized to the check valve, and it lasts like 30-45
seconds after the pump cycles. No banging, just loud vibration.


I had saved the original check valve, which the plumber had said was
still good. I put that back on, and all was quiet, until I noticed it
was leaking around the upper rubber flanges. I tightened it down and
now it's the same...massive vibration localized to the check valve
after a cycle, lasting around 30-45 seconds.


Any ideas what's happening?

I would be interested to know how it's hooked up to the sewer system. Is it a sanitary or storm sewer? Does it use a P/S trap? Is the pvc pipe sloped to the sewer line? Maybe the back pressure is causing problems in the check valve?

I am worried about some of the issues you describe, but (a) am a total novice, and (b) have no idea how the connection outside the house actually is set up. According to neighbors (all that have the same config) the sumps were hooked up during the home building process. I'm not sure to what system.

I was hoping it was something stupid I did with the check valve, since when we moved in, it was quiet for years.

Aa couple things you might try, first,they sell plastic check valves for sump pumps with a rubber flapper check inside. Also to isolate the noise, go to a auto parts store and look for a straight corrugated radiator hose, I use one 24'' long and put that in line directly after the pump. That should quiet your noises. Best of luck........

Bob Krueger said:

Aa couple things you might try, first,they sell plastic check valves for sump pumps with a rubber flapper check inside. Also to isolate the noise, go to a auto parts store and look for a straight corrugated radiator hose, I use one 24'' long and put that in line directly after the pump. That should quiet your noises. Best of luck........

Click to expand...

So, at the top of the check valve, REMOVE the rubber that comes with it, and replace it with approx 24" of radiator hose? Does that come in the right diameter for the top of a check valve/pvc? I have 1 1/2 inch check valve now.

And, so I understand, it is your feeling that the vibration is "normal" and I need to take steps to minimize the noise? I assume the radiator hose is to allow the check valve to move a bit and alleviate some of the intensity of the vibration?

Hello Morey:
Let's talk about loud sump pumps. The time and intensity of the vibration (after the pump kicks off, for 30 to 45 seconds) indicates to me the water is comming back around the check valve for some reason. If you want to make a very simple and quick test to see if I'm right, just take the cover off the pump, precicely measure the level of the water in when the pump kicks off, wait for the vibration to stop and measure the level of the water again. If I have the correct answer, when the vibration stops the sump will be fuller.
Now, sump pumps are noisy any way you look at them. That is why Bob Krueger said to use the corrugated radiator hose; its a type of vibration isolation. Another vibration isolation device is available from the heating and cooling folks; a 2" square by 3/4" thick rubber pad they use under the outdoor condensing unit to keep it quiet. You will need 3 of them to set the sump pump on. Check the suspension of the pipe again; PVC needs to be supported on every other joist to prevent sags in the pipe, and it should be supported by nylon webb, plastic plumber's strap or even springs about 1/4" below the joists. Any of those hangers will dampen the vibration and the space is more important than the hanger; it will prevent telegraphing the noise from the pipe.
The end of the sump pump line is supposed to be suspended above an open receptacle which is just an enlarged free standing pipe that should be about a foot long. That pipe will lead to an increaser (turned upside down), into a P-trap and then into the sewer line. Let us know how it works out for you.
Glenn

morey1 said:

So, at the top of the check valve, REMOVE the rubber that comes with it, and replace it with approx 24" of radiator hose? Does that come in the right diameter for the top of a check valve/pvc? I have 1 1/2 inch check valve now.

And, so I understand, it is your feeling that the vibration is "normal" and I need to take steps to minimize the noise? I assume the radiator hose is to allow the check valve to move a bit and alleviate some of the intensity of the vibration?

Click to expand...

Those radiator hoses come in different sizes, I have a 1 1/4'' pipe and found a correct match. The vibration and noise from the pump was telegraphing with the rigid pipe and the hose isolates that. Also a metal check will slam shut and you can hear that, the plastic & rubber ones made for sump pumps are a lot quieter. Most sump pumps have a 1 1/4'' discharge. Take a measurement of the pipe you are working with and go to the parts place, think you will find a match. good luck.

Let me correct myself. No, a leaking check valve is not normal and should be reparied. I was actually talking about all the other vibrations inherent with a sump pump. You may even want to take the check valve with you when you go after the hose; 1-1/4" pipe measures close to 1-1/2" on the outside and the inside diameter will not mic to an exact size. It is the sort of thing that makes a plumber's eyes cross.
Glenn