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jirocz
Feb 16, 2009, 12:21 PM
Hi
I have put in a new laundry room on the 1st floor in my home.
I have a utility tub drain, washing machine drain and I have a washing machine basin in case the washing machine breaks and starts leaking water, it will go in the basin and down a drain.
The 3 drains will ultimately go into 1 drain and tap into the drain from the kitchen.

My question is:

Utility tub will have a trap, run under the floor about 4 ft and connect to the basin drain, then connect to the washing machine drain.
Does or should the basin drain and washing machine drain need to also have a trap and their own vents?
Also, I was going to use an automatic vent so I don't have to go through the roof.
Where should I put the vent? I know it should go after the trap in the utility tub correct?

I will be running 1.5 pipe for the drain and it will connect into the kitchen drain line about 30 ft away.

Thank you in advance for any help

massplumber2008
Feb 16, 2009, 03:24 PM
JiRocz...

I strongly recommend that you run this in 2" pipe. I also don't recommend that you connect this into the kitchen sink drain... unless the pipe is 2" then that would be OK.

In terms of venting and traps:

The utility tub gets its own trap and its own vent (automatic or not). If you use an automatic vent then that vent must at a minimum connect about 6" above the trap. If individually vented system that connects to other vents then the vent must run at about 42-48" off the finish floor before connecting into the other vents... ok?

The washing machine also gets its own trap and vent. Here, again, If you use an automatic vent then that vent must at a minimum connect about 6" above the ptrap. If individually vented system that connects to other vents then the vent must run at about 42-48" off the finish floor before connecting into the other vents. The washing machine ptrap is at about 8-10" off the floor and the standpipe out of the trap is about 30" tall.

If these two will be close to each other then you can combine the waste and vents as drawn below and use only 1-2" automatic vent (AAV)..see drawing.

You will need to install a cleanout at the base of the pipe coming up to pick these drains up. A cleanout should also be installed at every change of direction and just before you make your connection into the main drain pipe.

The wash basin (washing machine PAN.. right?)you mentioned... if you connect this into the sewer system, then it will require its own vent and trap, but it will also require a TRAP-PRIMER. Here, the trap primer connects to a water line and it spits out a few teaspoons of water into the wash basin whenever the washing machine gets used to keep the trap wetted at all times. If the trap-primer was not installed the trap would dry out and sewer gasses would enter the home... a serious health hazard.. ok?

That means that I would recommend that you either connect a pipe to the wash basin and run it to the exterior of the building OR you could also install an automatic shutoff valve (see picture) at the washing machine pan.

Here the auto. shutoff (called a floodstop system) gets connected to the water supply of the washing machine and a sensor is laid into the pan. If water is sensed it automatically shuts the water supply to the washing machine. The system is not fool proof, but it is better than no auto. Shutoff... in my opinion.

Anyway... there is a start for you. Let me know what else you need...

MARK

jirocz
Feb 17, 2009, 06:08 AM
Mark,
Thank you very much for the quick and very informative answer.

I tried to make a drawing of my situation and going to try to imbed it.

The drawing shows what I was thinking of doing but figured I better research some more and ask some questions.

Let me know what you think of the way I was planning on doing this.

If my original idea seems OK to you, it would eliminate the need for the trap primer as I was going to utilize one trap and vent for the utility tub and one trap and vent for both the washer tub and washer drain.

I am trying to make this as simple as I can so I can try to hide the piping between the floor joices so I can finish the ceiling downstairs.

If what I was thinking is not OK to do, please let me know and I will go with your recommendation.

Thank you again for your expertise.

massplumber2008
Feb 17, 2009, 06:31 AM
Hi...

Sorry to say, but in terms of plumbing and plumbing codes what you propose there is not legal... in any way... :(

You cannot have a UTRAP... illegal.

Your vent exceeds the required 6 feet maximum distance from trap to vent.

You can't combine the washer pan with the washer unit itself.

I would go with information.. exactly as posted at my first post... ;) Combine the vents and install 1 AAV... ok?

And once again, consider increasing this drain pipe to 2"... you won't regret!

Good luck...

MARK

jirocz
Feb 17, 2009, 07:31 AM
That's what I needed to know.

Thank you very much again for all of your help. I will let you know how it all turns out.