Can a dishwasher and a washer share the drain?

[Sam Takoy]

Hi,

If my dishwasher is not far from my washer/dryer, can they share the drain with some kind of Y-shaped fitting?

Thanks,

Sam

[mike]

You've probably got only one pipe to the sewer line. So, all your stuff shares the same drain. It's all about volume vs size of the pipe vs restrictions so one doesn't back up into the other.

If you try to drain both at the same time, you may overflow something...maybe...

[mm]

My mother had a washing machine with Sudsmiser. It must have had two output hoses, one for the wash water, complete with soap, and another for the rinse water. The wash water went into the laundry tub. The rinse water went into a short pipe that fit into the laundry tub drain, passing right through the tub full of wash water. (Maybe like there were two drain hoses, there were also two drain speeds?? My mother woudln't care if a load took 60 minutes instead of 45.)

So the sink drain was able to take the entire output of the drain pump of the washing machine, without backing up. I also see laundromat and apartment hookups with no laundry tub, so I guess they can take the full output of the drain pumps too.

HOWEVER, in my house, the regular washing machine fills the laundry tub to a depth of 10 or 12 inches before the drain starts to catch up with the amount of water pumped out of the machine. Would it drain faster for some reason if the drain hose went straight into the drain pipe? Is there some siphoning effect that helps the drain along? I don't think so because I think those apartment hookups aren't air- proof at all. I think the bent drain hose just sits in the drain pipe.

ANYHOW, my question for you is, Is there any chance the clothes washer drain will back up into the dishwasher, which won't be on and won't drain until you turn it on. Is it possible for anything to back up into the dish washer, or is there something that stops that? And would the dishwasher part of the Y ruin siphoning that I speculated helps the washer drain drain faster?

Sorry I can't answer any of this but there must be people who have both connected like you want, or know the answers to my questions.

[HeyBub]

Volume-wise, probably.

A dishwasher drain usually goes to the garbage disposal to prevent hunks of left-over bacon (is there such a thing?) from clogging up the sewer line, or at least a p-trap.

[bob haller]

actually today near all dishwashers have grinder pumps, like small garbage disposal built into dishwasher.

drain water has no lumps

[Evan]

It all depends on what sort of laundry or apartment set up you are considering...

In a laundry often times the smaller machines are draining into larger size pipes that you can not obviously see...

The larger industrial machines are either on their own 4" or 6" drain lines or are emptying into a large drain trough located in the floor behind the machines where you can't see it...

~~ Evan

[DD_BobK]

The answer is all about the "fixture units"...... a d/w is 2 (I think) & a washing machine is 4 (I think).

Depends on the type of washing machine you have.

I had (& have) old school washers that used to dump into a laundry sink. The sink had a 1-1/2" trap leading to a 2" ABS line.

The sink would fill up rather deep but always kept ahead of the washer unless the "cross" in the drain had lint buildup. Lint buildup used to over flow the laundry sink a couple times a year. :(

The dishwasher was located about 15' away. The d/w flow "Y'd" into the washer's drain line about 12' from each machine.

I never got a backup or overflow due to simultaneous draining but I'm not sure how often they drained at the same time.

I measured the flow from the washer....my recollection.... the discharge was about 30gpm

To be absolutely safe & sure..... you need to check the drain piping size, determine its fixture units capacity & check that capacity against the fixture unit demand of the combination.

here's a link to capacity

if my numbers (2 & 4=3D6) are correct and the info at this link is correct (horizontal 2" line =3D 8 fixture units)

then you;re ok

Double check the numbers, I'd hate for you to have a flood. :(

cheers Bob