Sewer Smell

[Bob Denman]

I agree: A couple of bags of ice in the tank; seems to help keep the problems at bay!

[Koho Camper]

Took RV out of storage last night. Noticed a slight odor in bathroom so added ~1 gallon of fresh water and chemicals to black tank. Turned on bathroom vent and went to sleep in house. Walked into RV this am and the entire RV reeks of sewer smell - to the point it is not useable.

Yes, I did dump before storing - black first, grey second. Yes, I did add chemicals to tank before storing.

I'm trying to figure out what the heck happened? My RV is a new Delano (2020). We have put very little solid waste into the black tank in the three trips we have done, have always dumped before storing (black first, grey second).

Appreciate any insight here, particularly since I need to make a 3+ drive and a weekend of camping starting NOW!

[Bob Denman]

By turning on the vent fan; you probably were pulling fumes out of the black tank...
Did your toilet have a little bit of water in it? That would act as a barrier to prevent the fumes from coming into the bathrom.
(This is assuming that the sink drain isn't the culprit...)

[ArrrV]

New is the hint that helps. First, check your admittance valve (under the bathroom sink) and tighten if it is loose. If that didn't work--has it been windy, or even a steady light wind? Then likely culprit is the vent pipe being unable to vent because of the wind (same applies for smell when driving). Add a cyclone or a 360 vent topper. If no wind to block natural venting the vent pipe may have installation issues, too deep in tank, gap at roof, or other connection (or lack thereof) problems and you will need to take her in for service. Hope it's an easy fix.

[Koho Camper]

Originally Posted by Bob Denman

By turning on the vent fan; you probably were pulling fumes out of the black tank...
Did your toilet have a little bit of water in it? That would act as a barrier to prevent the fumes from coming into the bathrom.
(This is assuming that the sink drain isn't the culprit...)

Water in toilet bowl? Nope...also did not add water to sink traps for storage.

While I was working in my RV last night I was thinking "I love this thing, it still has the 'new car' smell!" Not anymore!

Many thanks Bob, appreciate the response.

[Travelin' Texans]

After fulltiming for 10+ years we never had sewer odors unless the galley grey tank was about full, it actually smelled worse than the black.
Traveled with the vents open, but put stoppers in all sink drains & plenty of water in the toilet, no odors.
Never had any luck with dumping ice in the toilet other than getting rid of a couple bags of ice. Dropping 2 -10lb bags of ice into a 50+ gallon tank I compared to adding 4 ice cubes to a tall glass of water, not much cooling & last about 20 seconds. I added 4-5 gallons of water & a good squirt of dish or laundry soap after dumping with much better results than the ice.
We had a washing machine draining into the bath grey so when parked connected to sewer the bath grey valve was always open or I'd be pulling the handle every other day from laundry & showers. I always dropped a sag in the sewer hose & never had roaches or rats in the tank nor ever heard of anyone that actually had that happen other than on the internet. But if it's on there it has to be true??

[Koho Camper]

Originally Posted by ArrrV

New is the hint that helps. First, check your admittance valve (under the bathroom sink) and tighten if it is loose. If that didn't work--has it been windy, or even a steady light wind? Then likely culprit is the vent pipe being unable to vent because of the wind (same applies for smell when driving). Add a cyclone or a 360 vent topper. If no wind to block natural venting the vent pipe may have installation issues, too deep in tank, gap at roof, or other connection (or lack thereof) problems and you will need to take her in for service. Hope it's an easy fix.

ArrrV - Thanks for the suggestions. Checked under the sink - no admittance valve, just the normal drain plumbing I would expect to see under a sink?

Wind - yes, but really just a gentle breeze.

Vent on roof - nothing special - looks like a PVC pipe with a "roof" over it to prevent water coming in. (Took pic with iphone, but even that is giving me fits this am!)

[JamieGeek]

Typically the bathroom sink also drains to the black tank. It is possible that your p-trap was empty allowing the vent to suck air straight from the sink (and thus the tank).

Make sure the sink has some water in it as well.

[Beau388]

Anytime I leave the coach for a week or more, I pour a little RV antifreeze in all the "P" traps and the toilet. I find it doesn't evaporate like water. 101 degrees F and 26% humidity will suck the water out of the "P" traps in a couple days. Good news no chance of mold.

[Travelin' Texans]

Originally Posted by Koho Camper

ArrrV - Thanks for the suggestions. Checked under the sink - no admittance valve, just the normal drain plumbing I would expect to see under a sink?

Wind - yes, but really just a gentle breeze.

Vent on roof - nothing special - looks like a PVC pipe with a "roof" over it to prevent water coming in. (Took pic with iphone, but even that is giving me fits this am!)

Follow the p trap to the piping & look up the pipe for a fitting similar to the picture below, that's an air emitance valve. Unless the sink vents through the same vent as the toilet or has its own vent through the roof there will be this valve under the sink.

[cbach]

Originally Posted by Beau388

Anytime I leave the coach for a week or more, I pour a little RV antifreeze in all the "P" traps and the toilet. I find it doesn't evaporate like water. 101 degrees F and 26% humidity will suck the water out of the "P" traps in a couple days. Good news no chance of mold.

Never thought about using it when it's warm/hot, but makes perfect sense...thanks for sharing.

[ducksface]

When we used to have another house in an area where 10 percent humidity was the highest of the year, we used cooking oil in the toilets and traps.
Doesn't hurt anything and never evaporates.
Ran water to fill the traps and toilet, capped it with an ounce or so of cooking oil.
There used to be some swimming pool stuff which floated on the water like oil but wasn't oil. Really truly added about 2 degrees f.

And
Buy a cyclone. Easy install.
Of course if it's sucking stank from the drains cyclones suck lots more stank....

[Bob Denman]

10 percent relative humidity?
Were you in a pizza oven?

Thanks for the vegetable oil idea!

[ducksface]

I

Originally Posted by Bob Denman

10 percent relative humidity?
Were you in a pizza oven?

Thanks for the vegetable oil idea!

Funny thing.
A bag of Portland cement is usually, maybe lawfully, 6 percent.
At lake Havaasu and occasionally here, the humidity is 2 percent.
So, the weather actually sucks the moisture from a bag of dry cement..


Heres an old pic from a nice sprinkly day in May....

[Bob Denman]

I take it that mold is rarely a problem...

[Koho Camper]

Originally Posted by Travelin' Texans

Follow the p trap to the piping & look up the pipe for a fitting similar to the picture below, that's an air emitance valve. Unless the sink vents through the same vent as the toilet or has its own vent through the roof there will be this valve under the sink.
Attachment 25837

Travelin' Texans - looked for the fitting per your pic. Its not visible - the pipe does run into the wall so it may be back there but not likely - so the sink probably vents through the toilet vent pipe as well, right? Thanks for the pic, much appreciated.

Tried a number of things to get rid of the smell. Finally added 1/2 cup Borax 1/2 cup Dawn and 2 gallons water directly down the toilet about 1 hour ago. That finally appears to be working.

Cant for the life of me figure out how this happened though. The RV was at the dealer for weeks (warranty repairs - which they didn't do yet even after 3 weeks!) and when I picked it up the smell was just a faint tinge yesterday. But by this am it was horrendous. A friend asked me if "one of the workers used your toilet?". I don't think that's likely but....

[Koho Camper]

Originally Posted by Koho Camper

Travelin' Texans - looked for the fitting per your pic. Its not visible - the pipe does run into the wall so it may be back there but not likely - so the sink probably vents through the toilet vent pipe as well, right? Thanks for the pic, much appreciated.

Tried a number of things to get rid of the smell. Finally added 1/2 cup Borax 1/2 cup Dawn and 2 gallons water directly down the toilet about 1 hour ago. That finally appears to be working.

Cant for the life of me figure out how this happened though. The RV was at the dealer for weeks (warranty repairs - which they didn't do yet even after 3 weeks!) and when I picked it up the smell was just a faint tinge yesterday. But by this am it was horrendous. A friend asked me if "one of the workers used your toilet?". I don't think that's likely but....

Quick update for anyone with stinky sewer smell. This worked WONDERS:

"Tried a number of things to get rid of the smell. Finally added 1/2 cup Borax 1/2 cup Dawn and 2 gallons water directly down the toilet about 1 hour ago. That finally appears to be working."

Many thanks to RT Bowlin (wife found him on YouTube in about 5 minutes after watching me try all "my" ideas to fix the smell issue for~5 hours) for the recipe. You can find his site here:

https://www.trbowlin.com/bio-geo-method/

Truly appreciate all the responses to my questions - off we go!

[Bob Denman]

Thanks for the update and solution, and congratulations on getting this problem "behind" you.