Our problem is our house is below grade for the sewer, so we have a grinder/pump in the crawl space of our house to eject all the waste uphill out. Everytime the pump shuts off, we get a tremendous bang (sometimes two) that can be felt all over the house. The rise from our catch in the crawl to the level where it leaves the house is at least 10 feet and I believe the bang is the waste backing up against the check valve, but I'm not sure. Does anyone know a way to quiet it down? Is it possible to not have a check valve?
The plumber that did all the work on our house has no idea what to do, but did add some sort of air valve in where he said we can go in the crawl and add air into the system with a pump. Didn't seem to help and I never have understood what he added or how it was supposed to work.
Any help would be greatly appreciated. Tired of hearing things go bump every time our pump turns off. Thanks!