This is our 15th night this season. First time happening:Strong odour (you know which one) from the bathroom - for the last 2 hours.We did nothing different today. This is our 2nd season with this TT. Prior to that, 4 seasons in an hybrid.Wife says the bad smell comes from bad seal/gasket. I said I would check on the forum; maybe you guys can come up with a number of reasons why it started smelling tonight. I wish I could tell you a bit more; but really, we use bathroom for #1s and #2s. If we need to use more toilet paper, we dispose of it in a garbage bag. We're camping with water/electric. No sewer. We arrived Saturday at 1 p.m. Now it's Sunday 11h45 p.m. We know it's not full.Can you guys direct to what you think could be reasons for this strong bad smell?ThanksMarc

If bathroom roof vent open it might be coming in that way

Smart! I'll do that and get back to you. It's windy tonight.Thanks.

we used a a couple cups of borax and a cup or 2 of cheap liquid laundry detergent in about a gallon of water each time we dump the tanks and start off empty. This works very well to keep smells down or non existent. if you are running a/c, check to see if the return air is sucking air from the bathroom.

Can you see bolts or nuts around the base of the commode? If so see if one or more is loose. If so tighten them up so they are evenly tight. This might pull the commode down on the seal. Don't overdo it.

Is there a check valve for the black tank vent?

URGENT HELP NEEDED - MAJOR SMELL FROM BATHROOM | Good Sam Community

12thgenusa
Explorer
Jul 11, 2018
SoundGuy wrote:
The only time the grey / black tanks should be completely empty is when you winterize, otherwise never. Once you've dumped & flushed either you want to add a minimum 10% capacity of the tank with fresh water and tank chem of your preference which you'll then start your next camping trip with.

Meh
Bobbo
Explorer II
Jul 10, 2018
maillemaker wrote:
What is an "AAV"?

Steve

An Air Admittance Valve is necessary under the cabinet holding a sink unless that sink's drain line is connected to the roof vent. Without some kind of air admittance vent, the suction of the water going down the drain would pull all of the water out of the sink's trap, allowing sewer odors to come up. The AAV breaks that suction. It is a one way valve, allowing air to go into the drain line, but not allowing air (odors) to come back out. If the AAV fails open, it allows air (odors) to come out. If the AAV fails closed, it sucks the water out of the sink's trap allowing air (odors) to come out. The solution for either condition is to replace the AAV. It is cheap and easy. It costs less than $10 at a big box hardware store, and just screws on.
MEXICOWANDERER
Explorer
Jul 09, 2018
Sometimes I need a reminder why I went the hideously expensive marine toilet route. Other than avoiding having my knees jab me in the chin this thread is an excellent reminder. May I wish you the best of luck solving your problem...
Happytraveler
Explorer
Jul 09, 2018
We have been using Aqua-Kem Deodorant blue cap bottles for 20 years or more. We flush with regular toilet paper and turn on the fan as needed. If it's hot outside we don't go chintzy adding extra bottles to the tank.So far no problems.
mtofell1
Explorer
Jul 09, 2018
I had something similar once and it finally went away after I filled the tank completely with water and chemicals and let it sit for a week. I figured something got stuck to the side of the tank.
SoundGuy
Explorer
Jul 09, 2018
maillemaker wrote:
What is an "AAV"?

Air Admittance Valve
Lynnmor
Explorer
Jul 09, 2018
maillemaker wrote:
What is an "AAV"?

Steve

This video should help you: video
maillemaker
Explorer
Jul 09, 2018
What is an "AAV"?

Steve
Bobbo
Explorer II
Jul 09, 2018
1. bad AAV
2. toilet not holding water after flush
3. sink or shower trap empty
4. bad seal between toilet and floor
5. blocked/dropped holding tank vent

(Over the past 10 years, I have personally had all except #2, pun, pun, and #3)

Be sure to check these for the gray tank too. It smells just as bad as the black tank.

If the plumbing system is working as designed, no "deodorizers" are needed. No plumbing smells will get into the RV (except when you open the toilet's seal to flush it with the exhaust fan running). If the plumbing system is NOT working as designed, no "deodorizers" will work.
drsteve
Explorer
Jul 09, 2018
Grey tank can stink just as bad as the black. If you never use your tub/shower the trap can go dry and allow fumes into the living space. Pour some water in your traps.