I have just had my furnace replaced with a high efficiency model. The drain line from the new furnace runs across the top of basement floor and into a floor drain. I want to install a new floor drain closer to the furnace room so it will take care of both the new furnace and any hot water tank pressure relief valve issues that may come up.
It looks like the plumbing under the floor passes right in front of the new furnace on its way to the main stack in the opposite corner of the furnace room. It seems simple enough to just break up the slab in front of the furnace and install a new floor drain.
It looks like it is all 3" ABS piping so I was going to cut into the existing horizontal pipe and use a 'P' trap and no hub couplings to tie it in. Any problems or issues with this? My main concern would be some kind of issue with a second floor drain leading into the main line. Is it acceptable to bury the no hub coupling? Any recommendations on what granular material I should, or shouldn't use, to back fill around the new piping?
Thanks very much.