Just want to know how you guys feel about 4" pvc check valves in sewer lines. We have a company here that really pushes them. My experience with them is that they seem to cause more problems than they solve. I guess if the ho would take the time to clean them or have them cleaned once in a while they would be ok but they almost never do. Plus if I don't know they are in there I tend to get my snake stuck in the line. The only place I could see using them would be if you are the low house on the block. and even then I have reservations about them. This company makes it sound like if you have a check valve in your line you will never have a flooded basement again which we all know that is a bunch of crock. This is the same company that I talked about in my other post about lying to customers.