Alternative Suggestions for Washing Machine Drain in Old House

[Stewsfarm]

Hi, always enjoy browsing this forum and have a question I could use help on. In short, in our basement, the washing machine (previously a front load) drained up and unit a stand pipe with trap that went into the septic line within the basement - about 5.5 feet above the floor. Because of the height, the standpipe is nearly up into the rafters in the basement (prob 7 feet height overall). To get the drain to that stand pipe, they added an extra piece of rubber hose. I'm concerned that it is pumping too high and / or hose is too long.

At the same time, on the other side of this room there is a finished bathroom area where the shower, toilet and sink is handled by a sewage ejector pit / pump. That pump drains up and into the septic line - same line as the washing machine now - just a different location along the line. They added a vent to the ejector pipe but it only goes outside and under an exterior overhang mudroom, etc (this is a 100+ year old house). I recently changed out the ejector pump and added a new check value and ball valve.

We are replacing the washing machine and i'm at a point where i'd like to make sure I'm changing things for the better. I have never liked the idea of the washing machine pumping up to that stand pipe. Also, I realize it should be 2" versus the current 1.5". Seems given i have the ejector pump, i should build out a generally correct washing machine drain, core through the poured concrete wall (would prob do 3" hole through wall), and run the drain to the ejector pump. I would then cap off that current stand pipe.

I know there are probably other details i'm leaving out. I'm just curious to see of those with experience in this area would say that makes sense to go this route. The ejector pump is a Zoeller 0.5 hp pump - i think just over 100 gpm. Washing machine instructions note having a drain with a capacity of 17 gpm. I realized I'd have to consider a scenario where the shower and toilet is operating at the same time - although it is a spare bathroom not often used. Would appreciate any obvious points I should consider. I added a rough sketch that i hope conveys the scenario.

Thank you.

 

[Stewsfarm]

Thought i would add a couple pictures - one of the current laundry area where the current stand pipe is and then one of the other side of wall where the sewage ejector basin / pump is that could be used to drain the washer instead of the current standpipe.

 

[Sponsor]

 

[Reach4]

VA is uses IPC code.

To do your proposal, you need a vent after the p-trap. That could be an AAV.

How do you service the pump on your septic pit?

While your current setup is not code, it works. I would try it with the 1.5 inch existing setup. I would consider adding a pipe support for the standpipe so that the plastic is not carrying that weight. I am not a plumber.

 

[Stewsfarm]

Thanks for the response. Could I clarify, in your non-plumber view, is it fair to say that the existing setup using that stand pipe up high up is not good given the distance the machine is pumping up? Naturally, life would be easier just to use that - my alternative is to go rent a core drill to get the pipe through the wall and to the pit. But maybe the way it is is not bad? When I removed the old washing machine, there was water sitting in the drain line between the washer and the stand pipe - and it didn't smell great - sorry of like a dunked up sink drain. This washer has been there for 10 + years. I'd rather do it right or the best i can while i'm at it.

As far as servicing the pit, my first encounter was not pretty - in many ways. The lid was metal and rusted. I removed the old pump and cleaned out out. I replaced the lid (with a plastic one - and seal), replaced the pump, checked the float alarm, changed the PVC fittings, added a check valve with rubber connects for removal and then a ball value above that check value. So servicing would be easier than the first time around.

 

[wwhitney]

The washing machine manual will list the height it will pump. If the standpipe is not above that height, it's fine to continue using (but its trap needs a vent). If the standpipe is above that height for the new machine, then you'll need to change it.

Cheers, Wayne

 

[Stewsfarm]

Wayne - i'm going to check on the height. Not sure where i could add a vent for that? Or, would the suggestion be to lengthen that section between the trap and the main line and then put a riser with a AVV?

 

[wwhitney]

Lengthening the horizontal port to add an AAV (at least 4" above the trap arm) would seem like the simplest approach. You standpipe is allowed to be 18" to 42" above the trap weir. https://up.codes/viewer/virginia/ipc-2015/chapter/8/indirect-special-waste#802.3.3

While you are at it, you could replace those unshielded rubber couplings (only rated for underground use) with shielded rubber couplings (Mission Bandseal or Fernco Proflex). In which case it looks like you could easily upsize the standpipe to 2".

Cheers, Wayne

 

[Stewsfarm]

I just thought i'd clarify by updating the one picture of the current set up where the washer pumps up to a higher stand pipe. This would certainly be easier than running a new line through the wall and over to the sewage ejector pump. If i'm understanding, if the washer can pump to this height (manual says 96") and the riser i have is OK, adding in a AAV after the trap would make this setup acceptable? I guess i worried that since this trap was right on the main line that it would suck the trap dry - but i guess that is the point of adding the AAV?

Also, is it OK that that trap is about the same height or level with the main line? If all other things allowed, should the trap be higher?

 

[wwhitney]

Yes, and yes. Your hose at the top of the standpipe should have an air gap.

Cheers, Wayne

 

[Stewsfarm]

Yes, and yes. Your hose at the top of the standpipe should have an air gap.

Cheers, Wayne

Appreciate it - and wanted to acknowledge your comment on the unshielded rubber couplings - i messed up on that one and will look at getting the correct ones on the ejector pump setup.

 

[wwhitney]

Also, is it OK that that trap is about the same height or level with the main line? If all other things allowed, should the trap be higher?

I missed this bit. As to the first, yes, assuming everything has the proper 2% slope. As to the second, I don't know if there's an upside to raising the trap, I don't have any direct experience with this particular arrangement.

Cheers, Wayne