Saturday, January 18, 2014


I am writing this post as a "public service" to other RVers. Newbies, Old-timers, Full timers, or Any-timers. 

We have been having an unpleasant problem in the RV lately, and I think I have finally figured it out. 

The problem was an ever increasing stink in the coach. 

Since it seemed to be coming from the bathroom, I assumed it was a potty smell.

We have been keeping the Fantastic Fan going almost all of the time, and I have tried several different air fresheners, but nothing seemed to help very much.

"Stinking" up the bathroom is a delicate subject. I just assumed it was something I would have to get used to living in such close quarters.

But, today, when we had not been in the coach for several hours, and we both came back at the same time, I noticed the odor was as strong as ever.  Yuck! 

Knowing neither of us had been in the bathroom for several hours, I knew the source of the smell could no longer be attributed to normal body functions of a member of the crew.

The stink has been gradually increasing over the last few weeks.  

Yesterday, I almost emptied the bays doing some more reorganization, but I also keep a sharp look out for the remains of some small critter.  No bodies were found, and the bay areas smelled fine.


Then it dawned on me. RV plumbing works just like house plumbing. What keeps the bad smells from coming back up the drains are the P-traps. Water creates a seal. If the P-trap dries out, gas from the waste tank come back up.

It turned out the source of the smell was the gray tank by way of the shower P-trap.  Because we are dry camping in the driveway of our house, we have not been taking showers in the Alfa. We think the P-trap dried out, especially after one of our trips down to the dump site may have shook some of its water down into the gray tank.  

This afternoon I put a dose of black tank treatment and a couple of cups of water down the shower drain.

No more stink!  What a relief. 

I know some of you dry camp all of the time. Has anyone else had this problem? 


  1. Sorry I can't help...but glad for the info. Glad you got the problem fixed!

  2. Yup..... you did find it! Good for you!

    another one we get is if the rig sits out in the summer sun for a few weeks of no camping, the toilet has a builtin "p trap" in the ceramic bowl that dries out. It can be filled back up again by pouring water with a watering can into the two small ceramic holes up near the rim.... voila! smell gone!

    Karen and Steve
    (Blog) RVing: The USA Is Our Big Backyard

  3. Good catch. We have used a product in our grey tank called Elemonate - smells like lemon and works great to deodorize the grey tank.

  4. Good catch! We forget that the grey tank can cause problems as well.

  5. There's also a vent plug under the sink that can be an issue. We had to replace ours.

  6. Absolutely gorgeous header picture!

  7. We have the same problem in our house. Nobody takes a bath so after awhile the p-trap in the bathtub dries out and starts emitting a bad odor. A few cups of water down the drain fix the problem.

  8. A bit off topic, but every day as a teacher, I encounter STINK. Picture 20 teenage boys sitting in the same air-conditioned classroom all day. The air gets a bit funky; farts trapped with nowhere to go. Teacher walks in, peewww!! What have you boys been eating?!?


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