SEWER SMELL

[Larry-P]

When running the Fantastic fan (with a rear window cracked open)we are getting a sewer smell from the bathroom. Upon further checking, the smell is coming thru both the shower & sink drains.
How is this possible when there is water in the P-traps. Sometimes this same thing occurs from the kitchen sink.
On rare occasions this also happens when just running the bathroom exhaust fan.
I've changed the air valves but this still happens. There is no indication outside or on the under belly that any thing is leaking. How is it possible for the smell to get past the p-trap.
Is there a sewer expert out there that I can talk to ??
I have a friend that occasionlly has the same problem.

[richfaa]

If you have the one piece underbelly you may well have several gallons of "stuff"trapped in there. They do a real good job of holding liquid.Look to see if there is a buldge in the underbelly and push on it.Our underbelly had many gallons of galley and gray water in it before the weight ripped it loose.

[DQDick]

First of all your rig isn't totally equipped with P traps. Your shower, for instance, has a funny substitue for one that can become clogged and be slightly open and your kitchen sink has a valve that can stick open. The shower thing is located on the ceiling in my basement and it is supposed to function as a replacement for a P trap. Ours got crud in it that kept it slightly open and so we replaced it and started using a screen in the shower drain. That screen is an eye opener. The one under our kitchen sink is supposed to take the place of a vent pipe and is supposed to only open to let air in when you dump the sink water. It's just a plug on a spring, however, and can stick open leaving a path directly from the gray tank to your air.

[richfaa]

Yes the one under the sink can fail.We have a spare on hand and did have one fail on the 06 3400.The galley tank can produce a nasty smell.

[Larry-P]

DQDICK,
I can understand what your saying about the shower drain not actually having a P-trap. However, the bathroom sink does have a P-trap & the smell still comes from the drain. How is that possible ??

What am I missing here.

[jcurtis934]

If you have the dreaded air admittance valves for any of the sinks, then when they open you have a direct connection to the grey tanks...ie, tank smell. Doubt that you are getting tank smell through a p trap...you may have rotting hair, etc inside the drain above the p trap that can smell the same way. air admittance valves rarely work well. John

[vangoes]

Larry P
I was having the same issue with my rig. I replaced the air admittance valves and that did not help, so I removed them altogether and put in a plug. Wahlah, problem solved!

[Overlord]

I'm going to go out on a limb and guess that you have a washer & dryer cabinet with hook-ups at the front of your 5er, but do not have a washer & dryer installed in your rig.

Flush the hot and cold water supply lines(I disconnected mine completely) that go to the W&D, and magically, your "stinky problem" will vanish.

See this thread: http://rv-dreams.activeboard.com/t50.../smelly-water/

Read through the entire thread, ...lots of suggestions about their problem, from flushing the hot water tank, treating the gray water tank, etc., etc.

In the end, it was the W&D supply lines filled with stagnant, stinky water that gets drawn into the rest of the water lines and output through other faucets. Do yourself a favor and just flush those lines.


....and I quote:

"I want to do a quick update regarding our smelly water problem. I want to thank Overlord very much for the advice regarding the W/D lines causing the smell. We flushed those lines 6 weeks ago and since then no more smell. We had lots of advice regarding tanks, water heater, source of water and none of those solutions kept the smell away for more than 2 or 3 weeks. I think the mystery has finally been solved. My husband will be doing a bypass of the W/D lines since we don't need them as soon as he gets some time.

Thanks again Overlord for your help. It was priceless!!!"

[WaltBennett]

Just to add some to this - the black tank vent pipe is near the ceiling vent. If it's clogged (mud daubers, etc.), the sewer gas has to go somewhere and it will. If it's not clogged, a prevailing breeze may push the gas coming out of it down your vent. One of those little finned, free wheeling vent caps will solve the second thing, and may help keep those odors going out the vent pipe instead of elsewhere too.

[JandC]

All good suggestions, especially the one about flushing out your gray tanks. About every other black tank flush (every other week) I flush out each of my gray tanks individually using my FlushKing. Also, once and awhile I will keep the galley gray closed for a couple days with chemicals in it prior to flushing it.