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tooltime 07-17-2006 03:14 PM

Drain for Washer?
Hello everyone,
This time I am looking for help/suggestions to put a washer/dryer n a basement with no floor drain. My main concern is for the drainage of the washer. All I have is the area for the sump pump.
The drainage system goes out the rear where I plan on putting the units, but it is roughly 4’4” off the floor. I do not know if it is feasible to tap into this somehow.
The other option I can think of is just draining it into the sump area (approx 18-20: across, about 3’ deep) but my concern there is the sump pump not working out of the blue, then having a flooded basement.
Idea’s anyone?
No, I don't know why there is duct tape there, was not ready to remove it in case bad things happen :D

manhattan42 07-17-2006 06:51 PM

The maximum vertical height a clothes washer discharge pipe can be is established by the manufacturer.

The dishcharge hose, though typically set for about a common standpipe height of about 36", does not have to be limited to that height.

Machines will often allow the dishcharge pipe to be connected to a drain 5' or higher from the outlet of the machine.

It may be possible, given your machine, to simply run the discharge outlet to the existing building drainage system above the 4'4" height.

Most plumbing codes require washing machines to discharge directly to the drain piping. But even if it is allowed to use a sump, it must be sized large enough and the pump volume big enough to move the large quantity of water that a washer produces when draining, but would still be a poor alterative to drainage system draining.

glennjanie 07-17-2006 08:50 PM

Hello Tooltime:
The picture of your plumbing could have been taken in my basement. I have an identical set-up. Manhattan42 is correct; I even had to put an extra hose on my automatic washer to reach the drain but it worked like a champ for over 10 years. The previous owner had their washer draining into the sump; I didn't want the sump working that hard so I changed it over. I wouldn't consider going back to the sump.

tooltime 07-17-2006 11:23 PM

Awesome, thanks to your post, manhattan42. I went and did a search, found this form G.E. While I presently don't have a washer/dryer in my posession, I will hope that all washer's will be pretty similar in discharge capabilities.


In order for the drain hose to function properly, the drain must be at least 30" from the floor and less than 8 feet high.
My cieling height is les than 8' so, to take a stab at it, I am figuring of tying into the black PVC (img above) branching off of it going to the left behind the main drain piping and then running a piece down to be able to hook the drain hose from the washer to. Using a check valve to prevent water from draining back into the washer drain hose.

Any opinions as to the best placement for the check valve? In the sketch I have it jsut above the "U" where the washer drain line will go.
Should I even bother with the "U", and just go with a check valve at the bottom and straight pipe up, cutting/connecting the washer drain line as close as possible?

Here is a quick sketch I tossed together to hopefully illustrate my idea.

That's great to know, glennjanie. My original plan was to put a small addition on the back of the house, but that's not looking very feasable at the moment.
Is your set-up anything like my proposed one?
I plan on building a base out of pt/covered with osb or ply so that the washer/dryer will be level, and off the floor from any seepage that occurs during heavy rains.

manhattan42 07-18-2006 07:39 AM

Won't Work
Your proposed plan won't work.

The drain must go vertically at least 24" or so above the horizontal branch and then connect to it with a trap above that level.

A washing machine must discharge into a stand -pipe by way of an air break.

What you have sketched simply will not work.

It won't be able to pump the water up through the trap....

You don't need any check valve...You need to have the standpipe and trap above the horizontal drainage branch .........

glennjanie 07-18-2006 01:42 PM

Hi Tooltime:
Manhattan is correct; since the washer drain is an "indirect" connection (the hose is simply stuck in a pipe loosely) the water would spray out around the hose in your illustration.
You do have an opportunity for a rather simple connection though. You can cut out the 45 degree ell in the plastic pipe and replace it with a wye. That will give you the 45 for the sump pump to go through and leave the straight part of the wye sticking up to insert the hose in. You may need to extend the washer hose (or get a longer one from the dealer) in order to reach the pipe. Caution: after installing the wye you should make the sump pump kick on just to be sure it doesn't splash out of the pipe opening. Normally, black pipe is ABS instead of PVC; make sure you use ABS primer and cement on it. In my opinion, the wooden floor is a little over the top but I'm not going to tell you not to spend your money. You may have a reason that I'm not seeing.

tooltime 07-18-2006 05:54 PM

Ok, now I’m really lost.

To tackle what seems to be the simplest solution,
drop a “y” piece on the black ABS that goes to the sump.
Run an extended hose from the washer into the upper part of they “Y” I just installed.
Go buy a washer/dryer and call it a day.

Any reasons I would not want a check valve on the abs pipe then?
My point of a check valve is to prevent water from back flowing down the pipe.
On my original thought, I figured there would be more pressure pushing the water through the check valve, than pressure of the standing water in the pipe. That would allow the water to discharge form the washer, but prevent water from backing into the washer at the same time. I also do not want the discharging water to find it’s way into the sump, otherwise might as well save the work and just drop the hose in there to begin with :D

I had also intended on it being a sealed connection, whether with additional pvc fittings, or a worm clamp.

I know I do not have 2’ above the abs.

The purpose of the base is to raise the washer/dryer off the floor a bit (2”-4” maybe) and making it level, as the concrete floor slopes to the sump.

Forgive my ignorance folks, for not seeing what should be so obvious.. I know this isn’t brain surgery or NASA type skill required :D

manhattan42 07-19-2006 01:38 PM

Here's one way to do it:

-The washer drain goes vertically to a point a above the horizontal branch where you can get at least 18" of standpipe above the trap weir.

-The washer hose must connect to the standpipe via an "air break" so that waste, sump or sewage water cannot be siphoned back into the washing machine and potentially into your drinking supply.

-The standpipe drain must connect to the horizontal sump pump branch using a Wye as Glennjannie stated, or must connect directly to the vertical stack also using a Wye. Attaching to the vertical stack would eliminate any need for any check valves.

The point is that the washer has it's own internal 'check valve' so none is normally needed in the discharge hose. And because the washer must be connected via an air break, any water that backs up via the standpipe-horizontal branch connection is simply going to spill out onto the floor and not back into the washing machine.

You need to understand that an 'air break' is a an arrangement where a discharge pipe from an appliance, fuxture or device drains indirectly into a receptor below the flood level rim of the receptor but above the trap seal.

In the case of a washing machine standpipe, the 'air break' is created thusly:

The washing machine pump only pumps the water to a point high enough that it can empty via gravity into an standpipe, which is an air break type receptor.

In your diagram, the washing maching was pumping the waste water directly into a waste pipe connected to the drain.

This is a major non-no because backflow or backsiphonage in your case can cause polluted or contaminated water to get back inside the washer and potentially into the drinking supply system.


tooltime 07-19-2006 04:01 PM

Awesome pics there manhattan42 !

I do understand what a wye is, and I also follow the issue of a standing pipe as you just explained it very well.
But don't I need 2’ of standing pipe to place the washer discharge hose? I do not have 2’ of clearance, I measured from the top of the abs to the floor joist above and I only have 1’.
I went and grabbed a shot, and took some measurements. This is what limited space I have to work with. I am not seeing anyway to get a 2’ stand pipe in here.
*the blue tape was there for me to write my measurments on.
Yellow-1’ from top of abs to flooring joists
Orange- 6’ from bottom of abs to floor
Green- is my 2’ mark down from the floor joists
Blue – 4’3” from the center of the access to the floor.

Originally I had planned to put the washer and dryer to the left of the piping, that is where the water lines already are… but I could relocate them to the right if necessary.

manhattan42 07-19-2006 10:01 PM

I beleive Ohio uses the plumbing requirements under the International Residential Code, and under that code, the standpipe for a washing machine must have a minimum height above the trap seal of 18".

The 'trap seal' is the height of the level of water in the trap. The standpipe must be at least 18" above that water level in the trap.

No where is 2' above the wye mentioned.

But it still does not appear that you have enough clearance because of these distance limitation to tie into the sump pump drain.

You could, however, make the connection by connecting directly into the 3" vertical waste stack.

Otherwise you'll just have to sell your house and move....:)

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