Installing NEW basement floor drain

Hello:
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.
Replies
Greetings r,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someone's attention that can help you with advice.
Cheers
when in doubt add garlic
I've done this, but not on a line serving a stack from the second floor. There may be issues with that, e.g., sewage flowing into the trap. You may be able to prevent this if you can slope the new drain line enough and use a wye and not a tee to connect it to the existing drain line. As for the furnace drain, what I did for mine was to drill a hole in the floor drain housing just below the rim sized to accept the 3/4" PVC (in your case, ABS) drain line from the furnace, which I ran under the floor as well. The fit was tight enough that glue bonded the joint tightly. If your's is deep enough (mine wasn't) you could also tee in at a level above the trap. You can bury no-hubs ("Ferncos"), but you should get the type with stainless steel sleeves protecting the coupling. (Your local code may vary.) I used pea gravel to backfill my work. No problems to date.
Mike Hennessy
Pittsburgh, PA
Thank you very much for your input.Just to clarify, the line in the floor I want to tap into doesn't have all the second (or first for that matter) waste flowing through it. The only thing flowing in this pipe in the slab is the existing floor drain and also what I think is the weeping tile from an addition put on 8 years ago. So I don't think sewage backing up into the trap etc. will be an issue as it doesn't happen with the current floor drain. I will just be adding a second drain to this under slab pipe.Based on some poking around I have been doing. My existing floor drain is definitely ABS. I could perhaps drill a hole in the side of the drain, and them ram a 3/4" steel rod through the sand under the slab and finished floor portion and on into the unfinished furnace room floor area. The distance between the furnace and the existing floor drain out in the finished part of the basement is only about 4'. This would allow me to just run my 3/4" furnace drain pipe into the existing drain, above the trap. Of course this wouldn't address any hot water tank pressure valve release flood issues but the finished floor is tile, I'm just not sure the drain is at the lowest point of the floor {don't ask, it wasn't me ;) }.I wonder if the under slab pipe is clay tile or it was all redone with ABS? I can't see any patchwork on the concrete in the furnace room except for right around the base of the stack. Maybe I should rent a pipe/cable locator and check it out, perhaps a new pipe was run but only under the area which is now finished. I am going to have to start researching ABS-clay couplings although I get the impression that maybe a BIG no-no or way beyond my skills. I have worked with clay weepers before and that was not much fun.Thanks again.
Ferncos will work for ABC/clay transitions as well. Clay is a pain to work with though. I usually cut them with a cut-off wheel in a 4 1/2" grinder. If work space is tight, I use a worn wheel so I can do it from the inside.
Mike HennessyPittsburgh, PA
Well that is good to know and as luck would have it I have just this MORNING bought myself a nice shiny new 4 1/2" grinder. No better way to break it in than cutting into a drain pipe!Thanks again.