I'm in a building with no drains. A sink was installed with a drain pump which pumps the water 20 feet to the ceiling then a couple of hundred yards. This was done before I came into the picture. I have never seen it work. The company who installed it came and looked at it (warranty had expired) and said they would replace the pump and they would send a quote. They avoided us and never provided a quote. Maybe they saw a design flaw. I took it loose and some parts fell from the check valve/backflow preventer. I replaced that, the pump will work once then it doesn't seem to open the preventer. It seems the pipe is filling with water then preventing the gate from opening. We have another pump which pumps the same height but not as far.