We are experiencing a problem with a very noisy sump pump and drain line. The drain, 1.5" black ABS, runs vertically up from the well to almost ceiling level, then horizontal the length of the basement (~14') turns a right angle, then runs down into a large drain pipe that exits the building. When it runs, which is very often right now, we hear a steady motor noise and rush of water. When it shuts off, we hear a loud bang. This is audible not only in the family room directly above, but two levels up in the MBR. I have tried inserting some styrofoam wherever the drain lines touch the ceiling or other fixed parts of the house to reduce the transmission of sound, but it has made little difference.
Answer:
In order to get rid of the vibration you'll have to introduce some form of rigidity to the ABS and the best way to do that is to strap it to whatever it's rubbing on. Another system is to introduce a radiator hose of the same diameter so the pump is not attached directly to the rigid ABS. There are rad hoses of the necessary diameter and they're quite flexible. I attached mine with hose clamps and it looked after most of the noise immediately.
