Odors from washing machine's drain pipe

[damraw50]

Well, after living in our RV for a while we think we finally figured out where the "stink" is coming from. Every now and then (more now than then ) we get terrible gray water odors throughout the RV. It appears as though they are coming from the drainage pipe to the washing machine in our bathroom. Is it possible that this was installed without a p-trap? If so how difficult would this
be to repair?
Any thoughts would be greatly appreciated.

Damon and Ellen

[Wayne M]

Damon and Ellen,
Check your manual, but I'm guessing it will tell you how to "sanitize" the washing machine, which should take care of the drain.

Look for something that will tell you how much, typically a cup or two, of bleach to put in the machine and let it do its cycle. No clothes, just the cycle. If the odor is that bad you may have to do it twice. We do it once a month and we have a P-trap. It keeps mildew, and odors, out of the machine.

Someone should come along soon and tell you how to put a "P"-trap in.

[njs42]

I doubt they left out the pee trap-----but that is what I thought at first.

Had the same problem----check to see if the pipe for the outflow is too long and is pushed beyond the pee trap. If so cut it off to about six inches deep in the drain pipe. We did that and have been odor free.

[Workshop]

I would guess that it is unlikely that the P-trap was not installed. This is a picture of my install. It is located behind a removal panel in the WD cabinet. Yours might be different and plumbed in the basement before it enters the tank.




I presently do not have a WD installed. My drain line is capped with a threaded cap and have no odors in the cabinet or in the unit.

As the photo below shows, in order for the waste gasses to enter the unit....it would have to get past the liquid within the P-trap. That would mean the liquid has either evaperated or 'pulled' out by pressure or possibly travel.





On my 2001, the WD is installed in the bath closet....the line to the waste tank serves as both a path to the tank and as the 'vent' line for the waste tank and exits on the roof.

Depending on where your unit is installed...front closet area or on the side of the unit near the bath...you might have an AAV valve installed that serves as a vent and it might be sticking open causing the problem. If you have an access, might want to look at whats behind it....but that might require the removal of the WD.

workhorse

[damraw50]

Thanks everyone. We found the p-trap and will check on the "outflow" pipe.
Hopefully this will help. Can't keep blaming the dog you know..

[squeak]

mine will dry out from not much use i will run the washer i load and the smell will stop

[dogpatch]

The smell is almost always caused by evapouration. Once the P-trap empties, it allows the gas/odor to pass back up the stand-pipe and into the RV. This is no different than your drain in the basement of your home. Water needs to be poured down the drain to fill the P-trap periodically for the system to work as designed. Doesn't take more than a few cups to do this. More will flush out the old stale water and renew the system.

[Wayne M]

I always thought I was unfortunate that my WD was drained into my gray tank. Now I think I understand why. Although gray tanks can also build up a smell, it sure isn't the same as the black tank.

I also remember having an RV where the WD was drained directly to the out-pipe and not into any tank. The drain valve had to be definitely opened when washing clothes, and now into the gray tank still has to be open.

Since we do not use ours that often I'm appreciative of this thread. We need to run it, or figure a way to fill the P-trap from time to time. We have been lucky with no smell, so far.

[njs42]

Since there seems to be some benefit from this discussion I'll elaborate.

We had a new coach, lots of odors in the W/D area, three dealer attempts to fix failed, so I called Splendide myself----they were very helpful and suggested the elongated drain hose remedy. It worked. Slendide gets high marks from me. Call'em.

During this time one person suggested for long term storage using a cup or two of anti freeze in the pee trap as it will not evaporate. It gets flushed out with the first use. Seems logical--probably works---can't hurt.

Then we found that when we ran our Fantastic residual odors from the roof where the vent pipes exited would be drawn into the coach if another vent was open. At a trade show I found roof vent pipe caps (they look like Darth Vaders hat only white). The claim was they would draw these odors away because of some venturi effect created in their design. With some skepticism (fool me once) I bought and installed them---they are metal, powder coated,they work, four years in and they are still shinny, they pivot freely and they draw off the odors and disperse them.

CW sells a similar plastic device with kind of a shark fin look which did not appeal to me but it may work fine for all I know.

Now we look to our dog "Doc"--(as opposed to each other).