Sewer Gas Smell

[davespann]

I made a trip from Lake Charles, La. to San Antonio, Tx. last week in my '71 overlander. My first stop I drained my holding tank and nothing out of the ordinary happened. The second stop in Houston I drained the tank and filled the trailer with sewer gas smell. How is the gas getting into the trailer if I have the toilet dump gate covered with 2 to 3" of water as a vapor barrier? I don't know what was different between the first and second useage.

Any ideas out there?.........Thanks.........Dave Spann

[Pahaska]

If you had a roof vent open, the smell may have been sucked down into the trailer from the roof vent on the black tank. Depending on what is open (vents, windows, door, etc.) and what is running (fans), you can get some pretty interesting airflow patterns.

[Chuck]

Here's another possibility:

I've found that if the sewer line in my older "sans-grey tank" trailer has the slightest obstruction, like a dip in the hose followed by a slightly up-hill trip to the dump station's sewer connection...anything that could make the slightest momentary resistance in the line, the black tank contents can back up into the shower. The output from the shower and sinks just connects directly to that sewer output...there's nothing to keep it from backing up, and the shower is below the level of the black tank, so....I now make it a practice to make sure that the drain stopper is in place in the shower before dumping. that will keep the yucky yuck from getting into the shower pan...but perhaps not as far as the drain trap. If that trap is full of sewerage, you'll smell it. So I also run water into the shower right after dumping (while still hooked up to the sewer) to make sure that the drain line is completely flushed out.

[bjstewart1]

Your smell could be coming from an over-charged battery. My wife and I were in Phoenix and for the first two days the smell of sewer gas was very bad. A stand pipe was near to our space and we thought it was the culprit. We had to keep the windows open but finally found that one of the batteries had over-charged from the Univolt unit. The battery had become so hot that the sides were bulged out and acid had boiled over into the compartment, hence the sulfate smell. One of the things in the solution was to buy some heavy duty batteries (deep cycle). Hope this does not occur again. Watch your charging system and make sure it does not over-charge your batteries.

[maznblu]

This forum is so great! On my most recent trip I had the same problem with a bad sewer smell in the front of the trailer after dumping on the previous trip. After finding no such smell in the bathroom (just at the front of the trailer) I just assumed it was coming from either the carpet (recently soaked) or the reefer because I had forgotten to turn it off between trips, so it had tried to power itself with propane (turned off). Now I have a couple of other possibilities to check. I had traveled with the roof vents slightly open, so I suspect the air circulation was the culprit.

Great info!
Eugenie

[Pahaska]

I have had just one case of bad odor with this trailer. The bathroom vent fan was on, the bathroom door was closed, and toilet paper had built up such that the toilet did not seal well. Air was being sucked in the vent and out of the black water tank.

I could see that when the pedal was released, the ball didn't close the last little way. I took a piece of wire and dug out the TP from the area where the ball seals and haven't had any problem since.

[davespann]

I suspect the smell could be coming from the tub drain. I thought the tub and sink had "p" traps to stop the smells from backing up so to speak? There are no clogs as I have been thru everything cleaning and replacing seals before my trip.

What does the "siphon valve" do on the back of the toilet? If the tub has not "p" trap then I bet the odor came thru there as everything else was closed with a water seal. I'll try the plug in the tub next time out.

Thanks again..........Dave Spann

[Pahaska]

In the summer heat, the P-traps will dry out if the tub has not been recently used. I put a little water in my shower trap when I get the trailer out of storage.

[escapeez]

My dad told me this little tip:

when you dump the black tank, be sure there's a bend somewhere in the sewer hose, not a crimp, just a bend, which can be flat on the ground but in an "s" shape and that keeps the back-wash airflow from the sewer from coming back full blast into the trailer....

I've tried it and it works.

[71tradewind]

I once heard that a table spoon of veggie oil in each drain prevents this from happening !!!!!

[jeff&jess]

Every time we flush the toilet, a bubble is formed and it "blurps" up all of the smells down below. This has only happened since our last emptying of the black tank. Even when I keep the lid closed, the smell still infiltrates the trailer.... (Although I'd prefer to watch when I flush to see that the TP doesn't get caught in the flapper, as was the root of my recent problem, so watching obviously makes the smell worse.) Anyone know why there's a bubble this time around? I read Escapeez' tip and we do have a bend in our hose. Black tank is closed.

Thanks for any advice!

Jessie

[Chaplain Kent]

You may be emptying you black tank too often and that is why it is causing an odor through your trailer. A suggestion is to not empty your black tank upon leaving a campground but when you enter a campground. You have put in those nice packets of chemicals and added water while flushing now you need time to agitate, or the motion of driving to stir things up, so to speak. This helps keeps the tank clean. You also need time for the chemicals to do their job.

[Foiled Again]

READ the label. I personally can't believe they still MAKE the stuff with the heavy perfume and formaldehyde, but it's in your standard "gift pack" when you buy a new Airstream AND is the cheapest RV specific stuff you'll find at Wal-mart and most RV stores.

Formaldehyde is embalming fluid, and if there's one thing I do not want to preserve for all eternity it's my effluvia!

Prior posters may be on the right track about emptying the tank too often; if so you could have the dreaded "black mountain". You need to get lots of liquid in there to dissolve and float away the solids. Also make sure no members of your family are disposing of any feminine hygiene products down the toilet! That kind of thing could lay around the bottom of the tank forever and !

I've found an oxygen/enzyme based chemical that is effective almost immediately (company coming), and I just use ordinary septic tank enzymes the rest of the time.

I'm also wondering if it's possible that your vent stack is clogged with hornets, mud daubers, etc. If the "whew!" can't float out of the top, it's got to go somewhere.

Test steps: get a wet dry vacuum and suck out your vent stack from the roof.

Re-Clean the seal of your flapper valve.

FLUSH your black tank. If your unit isn't new enough to have built in flushers, You might try a garden hose down the toilet with the flapper open, I suppose you could duct tape it to the end of a stick, and insert it down the flapper and move it around a bit. If you have a pressure washer wand, etc, that should work as a pretty decent rinser. As a last resort, you could flush it from the drain with the black valve open and a BIG pan under the drain (I'd use one of those plastic mortar mixing pans.) YUCKY job.

If you think you have the black mountain after draining and flushing, then fill the tank 1/3 full of warm water and dump a LOT of septic tank enzymes down the toilet. Wait three days, agitating the black tank (retract your stabilizers, jump up and down inside until the trailer is rockin'), then drain again.

I have seen cases where the sewer lines in the park may have a drainage problem and may even possibly inject methane gas into the line. Don't say I told you this but drain the tank without sealing the drain hose with the donut thingy! See if that cures the problem. I always leave that seal just the tiniest bit loose!

Paula

[Porky Pig]

Originally Posted by jeff&jess

Every time we flush the toilet, a bubble is formed and it "blurps" up all of the smells down below.

The burp is created by the natural gas forming in the tank. The gas should be venting out ... sounds like your vent tube is either clogged or came loose in the tank?

[crazylev]

The other day I was looking at the sheet for the actual No Fuss black tank flush and looking at the install sheet, the sprayer for that is installed about 2" from the top of the tank. The unit also has a vacuum breaker which gave me the idea that maybe some of what I sometimes smell is actually coming from the breaker in the No Fuss thing.

I always seem to notice that the smells come from around the vanity, which would make sense, since you can see the plumbing for this thing. At least I think it is the BTF I see. Either way, what I smell, isn't contiunous, just for a few minutes or so.

Just a thought.

Jonathan

[jeff&jess]

This morning Jeff got up to use the loo and found black-tank matter sitting in the bottom even with a flush, thus the tank was full. He emptied it, and then it was fine and normal: no 'burp' of water, no smell. I'm relieved but a little confused because it was emptied just a week ago and I wouldn't have thought we'd have used it that much since then. But maybe we did. I do use a lot of water. All of the advice above we've read and will keep in consideration, and thankfully for now all is normal again. Thanks!!!

Jessie

[howco]

This stinks..............

[Snaken49]

Originally Posted by howco

This stinks..............

These two products will eliminate your waste tank smells.

ROOF VENT

https://store.airstream.com/product_...roducts_id=249

3R PUROGENE ODOR CONTROL

http://www.3rodorcon.com/id3.html

[Gbg]

We have sewer gas smell and have not even used the toilet! Will check battery .