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Toilet Odor Solution

19K views 21 replies 17 participants last post by  Rubrhammer 
#1 ·
In 2006 and 2007, we had some horrendous odor problems with our Thetford Aqua Magic IV RV toilet. The toilet had water in it, which seals the tank quite effectively from the toilet - but the odor was still coming into our living quarters.

I cleaned the tank several times, and we tried several types of chemicals without any luck. It stank.

Thinking that the odor might be coming from where the toilet connects to the floor and tank, I replaced the closet flange seal - twice. This didn't help.

Then, thinking that just maybe the black water tank roof vent was clogged, I ran an old piece of hose down the vent pipe from the roof. Again, no help.

I checked the bathroom vent fan, and found that it WAS miswired, and blowing IN from the outside - from right near the vent stack. I fixed this by reversing the wires, but the odor remained.

I checked all the hoses for cracks, and tightened all of the hose clamp connectors at the tank and the toilet, although all seemed to be good and secure. No help.

I pulled the belly liner to inspect the tank and fittings directly, and found no evidence of leaks or odor.

Finally, in the summer of 2008, I solved the problem.

There is an overflow tube that extends from right near where flush water enters the top of the bowl directly to the black water tank. This is apparently intended to keep the toilet from overflowing if there is a small leak in the water valve.

The tube is curved, forming an "S" trap. If there is no water in the "S", there is a direct passage between the black water tank and the bathroom. Thus - BAD odors in your living quarters - regardless of what chemicals are in the tank.

To fill the "S" with water, simply fill the toilet to the brim. Let it stand for a couple of minutes to make sure the overflow trap is filled, and flush it down. Then, just use the toilet normally. It would probably be a good idea to repeat this a few times during the camping season, just in case the trapped water is sloshed out or evaporates.

At any rate, we have had NO ODORS SINCE WE STARTED DOING THIS!

For a diagram showing the overflow tube, see:
http://www.thetford.com/HOME/PARTS/Permane...18/Default.aspx

PALOD
 
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#6 ·
Interesting. No odors here but Ill check it out.

Thanks!
 
#15 ·
Wow... my vent fan was wired backwards too! I wonder how many Gilligan missed! We had the same odor problem. We also found another odor problem that some may have. Ours is a 28FRLS. There is a separate vent for the kitchen sink grey water that goes up behind the fridge. (we found this out because the fridge broke and while they had it out I got to clean up the wiring and found the pipe floating loose) Even though the pipe vents outside, it's pretty close to the bathroom fan, so when it was sucking air in... it was sucking in the smelly air from the grey water...
 
#17 ·
Hey, after spending xxxxx dollars on the trailer, I am going to use the throne. To me, this is one of the reasons to own a trailer.............to avoid sharing use of a public one and to avoid using a gasket if I had to.
 
#18 ·
Throne??? That might be the throne for the Munchkin King of OZ, but doesn't exactly scream comfortable for anybody my size. I was kidding about the no poopin rule. I will say that while at a CG with nice clean bathrooms, I will most definately make the trip, but I see little success making my wife and kids do the same. Besides, like you said, thats the most expensive toilet I own.
 
#20 ·
I m just thinking. Stated to fill toilet to allow water to run in the tube which is where odor is coming from. Now I see a winterizing issue with the water in that tube.

Looking at the diagram, I even doubt the existence of it because on the parts list is says N/A, not applicable.

I know you no longer have a odor problem, but................

I m just wondering out loud

John
 
#21 ·
Well, perhaps "throne" is not the most appropriate of terms. But you knew what I meant!
 
#22 ·
I haven't had the odor problem but it may be because when I'm dumping the tanks I have the DW fill the bowl a couple of time to give the tank a flush after it is emptied. I do the same with the gray tank with the sinks. This way there is always fresh water in the traps. I didn't know about the overflow tube so I guess dumb luck plays in my favor again. Thanks for sharing your find.
Bob
 
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