Draining laundry sink into washer stack?

glamgirrl

I'm installing a laundry tub next to the washer in my main floor laundry room. These are photos of the current set up...the water comes up from the basement by hoses to the washer. Then there's this other, extra cold water copper pipe sticking up, don't know why , but I'm hoping I can use it to get cold water at the laundry tub. Hot I'll figure out later. (It came this way when I bought the place-I didn't do it!)

I'm trying to figure out the correct way to drain the laundry tub into the washer stck...do I put the wye in above or below where the washer drains. I know the washer has to drain at about the height is now, but I could extend the pipe up about a foot if I need to drain the laundry tub above it. My question is- if the tub drains above the washer, is the water fromt he tub really going to make it all the way up there to get to the drain? Seems wrong to me...

I'm thinking it would be better to drain the tub below the washer (like in my rudimentary diagram-I'm no artist). Is this code acceptable? Will it work? Are there any issues here I'm not aware of? I wonder about the washer backing up into the sink when it drains- is there a way to avoid that? Some kind of valve perhaps? There doesn't seem to be a vent stack here- just the drain. Although the kitchen sink is on the other side of the wall..I bet it's in the wall somewhere.

The other image is of the P-trap under the sink...I've only dryfitted it-does it look OK?

Thanks for your advice folks, I'm pretty handy, but mostly with carpentry so far.

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hammerlane

I dont seea vent for your current washer standpipe.
By tapping into that washer standpipe for the laundry sink, the p-trap for the laundry sink may get siphoned out when the large flow of water from the washer discharge begins flowing.

Bud Cline

I can't understand how the washer drain is working now. If that drain system is closed where is the vent coming from?

I also can't imagine how you would drain the sink into the existing drain "above" the washer drain, how's that gonna work? The sink drain to the drain line must be lower than the bottom of the sink, no?

Doesn't water still run downhill and drain by means of gravity or has Barrie changed that too?

What on earth am I missing?

hammerlane

You're right Bud. The top of that Wye looked to be capped or has duct tape on it. Also the branch of that wye where the washer drain attaches to looks to have a trap adaptor on it sealing it???

Bud Cline

There is a reason "all" washer drain hoses come with a goose-neck on the end. That is to hang the drain hose in an open standpipe. The open standpipe serves as a secondary vent. I don't think the standpipe should be closed off for any reason.

If the standpipe was open and the washer drain had the original gooseneck to hang in the standpipe, then the sink drain could be cut in below the bottom of the sink somewhere and all should work okay. In reality there should also be a vent stack near that drain line that goes all the up and out of the building.

There also seems to be a missing trap for the standpipe.

hammerlane

They are using that trap adaptor because they are draining into the Wye branch. Cut that Wye out and just like you said hang the hose.

Bud Cline

Looka as if the hose has been altered already, maybe ruined.

Anti-wingnut

You may want to call a plumber, there are several decencies with your system as it is:

1) The supply pipe should be supported for safety (broken pipe) reasons.
2) The drain stack needs a vent. This could be as easy as installing a AAV at the female pipe fitting now covered with duct tap
3) The washing machine needs a trap
4) The tub will need to drain into the stack below the washer trap. The trap arm of the tub may need a AAV so that siphoning will not occur. I do not believe that the stack is adequate large by code to act as a wet vent for the tub. While it would not meet code, you may be able to use the stack as a wet vent with very little deleterious effects

glamgirrl

"There is a reason "all" washer drain hoses come with a goose-neck on the end. That is to hang the drain hose in an open standpipe. The open standpipe serves as a secondary vent. I don't think the standpipe should be closed off for any reason." The end was taped when I moved in, since the washer works fine, I never removed it, fo fear of what I might find. You think it should be open?

If the standpipe was open and the washer drain had the original gooseneck to hang in the standpipe,(the drain is attatched into the standpipe, not loose) then the sink drain could be cut in below the bottom of the sink somewhere and all should work okay. In reality there should also be a vent stack near that drain line that goes all the up and out of the building. I think the vent stack is inside the wall, because the kitchen sink is on the other side of the laundry room wall.

There also seems to be a missing trap for the standpipe.[/quote]
There is a trap for the washer under the floor in the basement.

So, can I just tap into the standpipe with a wye below the washer drain, or not?
Thanks,

Bud Cline

I would say YES.

glamgirrl

Thank you Bud! Much appreciated!
I thoguht that would work, but it's good to get other opinions too, right?

Bud Cline

As long as the drain is now accepting the high sudden volume of water being discharged from the washer then that water shouldn't back up in the sink.

If it was me I would re-install the washer goose-neck and open the top of the drain stack to hang it in, thereby affording additional venting.

Anti-wingnut

I would still recommend getting a plumber in

1) If the stand pipe is serviced by a trap, then the location of the trap is much too low

2) We do not know if said trap is properly vented

3) If the stand pipe is serviced by a trap, what is the purpose of you adding a trap to the tub? There is none, because the drain circuit is already trapped.

4) There is no need for a "secondary vent". In fact, such an application is precluded by code. A vent should either go to atmosphere outside the house, or be protected by an AAV

What you have now is a complete mess, and should be cleaned up

broox

Tie into the standpipe. It will be fine. You could use a tee or a wye/combo to tie in. You do not have to put a trap under the sink, but there is nothing wrong with using it since you already have it. Good luck.

glamgirrl

I realize it's probably not needed, since there is one just under the floorboards...not too low for the washer, but it's more in case I drop something in the sink- i can fish it out at the P-trap under the sink.
Thanks for all the advice fellas, I think I've got it now.
And, Mr. Anti wingnut, thank you for your opinion, but if I could afford to hire a plumber, I wouldn't be asking how to do this!