Black Tank Odor

webers3

I know this subject has been covered in many posts, I’ve looked through many of them but most talk about odor when flushing the toilet or odors coming from the gray tank due to dry p-traps.

I follow the protocol of making sure there is water in the toilet bowl and in the p-traps and the dump valves are closed, I dump the tanks every day and flush the black tank after each dump but yet I have a strong odor in the bathroom.

Some background: I have been work camping for over 2 months, I do not have an A/C so on a hot days I turn on the exhaust fan (I have a 320 with fantastic fan) before leaving for work, this is when I would find strong odor in the bathroom when I return. The fact that having the exhaust fan on resulted in the odor in the bathroom was baffling at first but that led me to believe that maybe the odor is coming from around the seal on which the toilet sits. I did some simple tests to prove this and have come to the conclusion that this is the case.

So not knowing much about plumbing in the T@B, my question is: is the toilet mounted on a seal as you would have in a household toilet? What is involved in removing the toilet and re-applying the seal?

Denny16

Are you leaving a window slightly open when running the exhaust fan?
if not, the fan is trying to find some makeup air to replace what is being forced out, creating a pressure difference between the cabin and the tank, and you are pulling vapors out of the tank through the toilet and sink drains, even with water in them, gas can bubble up and out.
cheers

4ncar

Yes, it is mounted just like at home, however, the o ring is made of foam, not wax. The stool pulls off the base just as a home toilet does; 2 bolts at the base of the toilet & then pull straight up.

webers3

@Denny16 The windows are open, in my test I have made sure there is water in the p-trap and in addition I covered the drains with heavy wet cloth and the toilet bowl is half full, I am sure the fantastic fan is not strong enough to do what you suggest

Denny16

Twas just a thought...   
cheers

jkjenn

You could have some pyramidal developing if you don't use enough water. I think it seems to dump better when closer to full because there is more of vacuum effect when you open the gate.

webers3

@4ncar foam O ring instead of wax, that's interesting, foam can't provide a tight seal as wax, can it be replaced with wax?

pthomas745

Is this a sewer odor?  Or an acrid smell?  If your gray tank is empty, whatever deposits inside it could be fermenting.

Sharon_is_SAM

Jkjenn And pthomas745 have good points.  Solids end up sticking to the sides of the black tank if inadequate volume is available before dumping.  If you aren’t careful, same can happen with the gray tank.   Also, are you using any kind of tank additive like Happy Camper?  You can use it in both tanks.

webers3

 @Sharon_is_SAM Yes I realize there are odors in the black and gray tank, I am trying to determine how they are getting out when as I indicated I have water in the toilet bowl and in the p-traps. @4ncar indicated that the seal on which the toilet sits is made out of foam instead of wax, foam can not provide a good seal, I will look into replacing it. Thank you

Dalehelman

In my experience over the years. The foam seals work very well. They are closed cell. If it happened to move out of place during installation that could be an issue, but it would probably leak around the base. IMHO I would not try and replace it with a wax seal. On occasion we have used an air freshener in the bathroom.

jkjenn

I would start by filling your tanks with water and a good treatment like the Valterra blue liquid stuff. And let it sit for most of the day.

Next, don't dump until almost full and make sure that your ratio of water is at least 1/4 water to waste.