"That" odor we all hate......

[Ncbob]

While septic systems aren't new to this ol' redneck...holding tanks are a bit different in that one sleeps a bit closer to the holding tank. Septic systems are pretty much anaerobic (without oxygen availability or venting) while our Black water tanks are aerobic because they're vented to atmosphere.

Thinking it was my venting system which was causing the problem I fumbled around for quite a while before the old proverbial light bulb lit over my head, thanks to an archived post by none other than our resident Guru, Richard Bowyers also known as Driving Miss Lazy.

Now I have no idea what brand of toilet Richard used then but his bringing my attention to the overflow holes in the bowl made me realize that they vent directly to the tank...bypassing that very nice contoured valve in the bottom of the bowl.

Once I placed some aluminum tape over the holes (the type used to hold fiberglass
A/C ducting together) my problems ended.  For the record my toilet is a Sea-Land.

DML covered his overflow holes with silicone compound for a permenant fix while I just opted for the tape as a temporary measure to validate the theory.

If this helps any of you...pass the judo's to DML as I am doing here.  Thanks Richard!

NCbob

[Ace]

OK Bob I'm glad you had you fill of the smell and also glad you covered it up but I would think that Sea Land or any other mfgr. of toilets made them the way they are for certain reasons. Putting silicone or tape over the overflow is nothing more than a band aid.  May I suggest looking further at your toilet installation or maybe even the way your black tank is vented? I know the chances of an overflow is pretty slim but there have been instances where a water pump has gone haywire along with a foot valve sticking and allowing  water to run continuesly while nobody was home which would have made a real mess had it not had an overflow. I hope this never happens to you or anyone else for that matter but covering up your overflow to keep the smell OUT will almost always allow your floor to become a drain and you DO have some nice wood flooring!
Again, check your venting to keep the smell from returning in. If your getting a lot of it back in then something else is NOT working. My toilet dumps into my black tank with a slight elbow and if my arm was skinny enough I could probably reach in and grab you some gunk. Bottom line is, I get no smell returned back thru the toilet. My vent is on the opposite side of the toilet inlet of the black tank and it goes DOWN thru the bay floor where as most vents go upward! ONLY smell I get once in a blue moon is when I forget to run water in the shower when it is parked for long periods of time. The "P" trap goes dry and allows an odor thru the shower drain but as soon as I run the water, it's gone gone gone! Remember, I have ONE tank for both gray and black!

Anyway... nice hearing from you again!

Ace

[DrivingMissLazy]

Thanks, Bob for the credits. LOL.

I suspect that there is a trap built into the overflow of all the RV toilets. I really do not know how water gets into the trap to fill it in order to eliminate oders coming up into the coach. If a flush hose was used to fill the trap, I suspect the problem would disappear until the water evaporated. 

Richard   

[prevost82]

Bob ... I also have a Sealand and mine does the same thing every now and again. From what I read on other RV forums this is a common problem with Sealand toitels because there no water trap in the overflow line. I plugged mine off too.
Ron

[Hartley]

It's an overflow drain, Not necessarily a vent. Unless it was intended to keep the pressure
from building up in the tank and causing a whoosh effect where what is supposed to go down
comes up quickly when you try to flush.

My Thetford Aria does not have an overflow drain or vent and does not vent back into the coach
in any way. The newer toilets have better control over the water valves than the manual pedal flush systems that have a history and water valve problems just by their design.

If the pedal gets out of adjustment or the valve messes up you have a water overflow problem.

Been there 3 times with a Sea-Land toilet on another coach. The pedal would stick and water would run down the hall and out the front door down the steps.

Not my idea of a fun day....

[Beatenbo]

Hey Bob, I've had 2 Sealands and no prob. We have about gone crazy with the Thetford on my C3. We can't figure what the deal is. It's plumbed and vented with the same material and tanks as the last two. Had almost considered Jerkin' out and replacing with a Sealand. Gonna check this out. BTW my 200th post. Have a good day Bob, Cottontop

[Ncbob]

I have to admit that I'm not the culprit who installed this rig...it came with the pacakge.  But had I installed it there certainly would have been a trap.

That being said my only course of action to test my theory was the tape...it's not permenant and can be easily removed or punctured in the event of a potential overflow.

I just thought I'd throw the info out there for anyone having a similar problem.

NCbob

[DrivingMissLazy]

it's not permenant and can be easily removed or punctured in the event of a potential overflow.

My plan, in case of a potential overflow, was to turn off the water pump. LOL
Richard

[superpickle]

I smelled that on a Jet Blue flight... Flite.... Trip.. Thought it was a New kind of Air Sent they were trying out 

[gus]

Even though I have a Thetford toilet this is a new idea to control the odor I've had off and on since getting my 4104 two years ago. Where are the overflow holes on a Thetford? It is probably 1995 vintage.

It came with a water pump switch installed under the kitchen sink. I moved it to the toilet compartment, not a chance of ever having a flooding problem if you turn off the pump.

[pvcces]

Since our toilet is inside our shower stall (the room is large enough for both), we just unscrew the shower head from it's hose and turn on the shower water while aiming the hose at the small overflow hole. We do this once each trip and it's never been a problem since we started doing it.

The overflow has it's own trap which will dry up if not used for a couple of months. The jet of water refills that trap.

For what it;s worth.

Tom Caffrey

[DrivingMissLazy]

What I have always wondered is how the manufacturer of the toilet ever expected this trap to get filled with water. I do not recall ever seeing anything about it in any instruction book.
I know that once I found the source of the odor after many years and several different motor homes, I made sure it would never ever bother me again. I was more than willing to take a chance on an overflow, since I had never in 30 years ever seen a toilet overflow. A silicon plug made sure it would never smell again.
Richard

Since our toilet is inside our shower stall (the room is large enough for both), we just unscrew the shower head from it's hose and turn on the shower water while aiming the hose at the small overflow hole. We do this once each trip and it's never been a problem since we started doing it.

The overflow has it's own trap which will dry up if not used for a couple of months. The jet of water refills that trap.

For what it;s worth.

Tom Caffrey