Sewer oder in trailer

[Cubman9000]

Hello, New to forum. We have a 2006 Designer 36 RLTS. Sometime when we enter rig we have a sewer oder. Not all the time. It doesn't make any difference if tanks are full, half empty or empty. I'm thinking the vent under the sink not working correctly? Any thoughts as what to look for?

[mike837go]

Originally Posted by Cubman9000

Hello, New to forum. We have a 2006 Designer 36 RLTS. Sometime when we enter rig we have a sewer oder. Not all the time. It doesn't make any difference if tanks are full, half empty or empty. I'm thinking the vent under the sink not working correctly? Any thoughts as what to look for?

Vent UNDER? the sink.

There shouldn't be one.

If there is an open waste pipe (even an admittance valve) it has to be above the top of the sink.

Cap it or find out where it is supposed to connect to.

[PlayersZ28]

Do you have a roof vent near the stack exit that is open when you smell the odor?

[Rustysocket]

Just something to check, and it is likely not your issue but:

I had a neighbor who called me over the other day for the same exact reason. He was getting a strong odor that he described as being like a sewer pipe.

When I entered the trailer I knew exactly what it was. His batteries were cooking and gassing off. A cell had shorted out.

Anyway, just check your batteries and make sure they are not hot.

[Subaru297]

We have two roof vents near our vent stack and if the wind is blowing right and the vent fans are operating they can pull odors into the trailer.

One other possibility....

Cheers

[00buck]

If the gray tanks get too funky they can smell like sewer gas too.

Stick your nose over your sinks and give them a whiff.

If it's there- I usually sanitize with a heavy dose of bleach in each one.
Add bleach, fill up tank, let sit, then drain. Works for me.

[norty1]

Yes the under sink valves are under many rv sinks..Called AAVs Air admittance valves. They can fail to seal sometimes and can admit some foul fumes. They can be tapped or even cleaned. Just a ball valve that may fail to seat.

https://www.bing.com/search?q=air+ad...NiUK6O&PC=DCTE

Here is one on my rv.

[bankr63]

Originally Posted by mike837go

Vent UNDER? the sink.

There shouldn't be one.

If there is an open waste pipe (even an admittance valve) it has to be above the top of the sink.

Cap it or find out where it is supposed to connect to.

In the building code, yes. AAV's, where permitted, should be located above the spill level of the associated fixture.

In the RV code...
Oh wait, we don't need no stinkin' RV code...

(Pun wasn't intended, but it works...)

Cubman, one other modification that many say works well. There are vent caps that can prevent backpressure through the roof vents (if equipped). They work like an airfoil to keep constant negative pressure on the tank stack - sucks the odors out of the tank instead of letting them backup into the trailer when the wind is right. I haven't personally tried them, but did a bit of research and a lot people believe in them. Is on my future mods list.

https://www.amazon.com/360-Siphon-RV...ank+vent+cover

[Cubman9000]

Found It, The admittance valve rubber seal was gummed open. Cleaned it and now it seals. Thanks for the help. Happy trails.

[abarkl]

Originally Posted by Cubman9000

Found It, The admittance valve rubber seal was gummed open. Cleaned it and now it seals. Thanks for the help. Happy trails.

Ours has one on the grey and one on the black tank.

[homer1959]

Originally Posted by Cubman9000

Found It, The admittance valve rubber seal was gummed open. Cleaned it and now it seals. Thanks for the help. Happy trails.

How did you get it out ? Is the AAV glued on the drain pipe or screwed on the pipe, or just press fit on the pipe ? thanks

[pop up pilot]

Thanks, I had the issue, tried several things, never thought of the AAV.

[Cubman9000]

Originally Posted by homer1959

How did you get it out ? Is the AAV glued on the drain pipe or screwed on the pipe, or just press fit on the pipe ? thanks

Mine was screwed in a riser just behind the sink

[namusmc65]

Originally Posted by Cubman9000

Mine was screwed in a riser just behind the sink

Had the exact same issue. Put on a new valve under the sink and all is well. Probably should have kept the old one and cleaned it up for the next time but didn't. Fairly inepensive so will just get a new one if it should happen again. Just a simple screw off and screw back on.

[mike837go]

Originally Posted by bankr63

In the building code, yes. AAV's, where permitted, should be located above the spill level of the associated fixture.

In the RV code...
Oh wait, we don't need no stinkin' RV code...

(Pun wasn't intended, but it works...)

Cubman, one other modification that many say works well. There are vent caps that can prevent backpressure through the roof vents (if equipped). They work like an airfoil to keep constant negative pressure on the tank stack - sucks the odors out of the tank instead of letting them backup into the trailer when the wind is right. I haven't personally tried them, but did a bit of research and a lot people believe in them. Is on my future mods list.

https://www.amazon.com/360-Siphon-RV...ank+vent+cover

It's spelt steeekin' if'n you wanna quote the move....

And, yeah I totally forgot about how building codes influence the construction of RV's.




Glad to hear all is OK now.

[pop up pilot]

I have a 2008 pup, and I have no AAV. The sink goes straight out a drain line. The shower, on the other hand, drains into the grey water tank, I found a standard P-trap on the shower. Since I seldom use the shower, the trap dries out, and any odor in the grey water tank goes through the drain line and into the trailer. Although the grey water tank has an outside vent, the drain line offers a much larger opening. I would have preferred an AAV.

[tularockstar]

Just curious, but how often do you do a thorough cleaning of the black tank? I was under the impression that this is an annual task that an owner should perform. After you have checked for appropriate venting of the tank, a good cleaning of the black tank would be a good idea. Over time, the tank starts to collect residue (not to be gross) and a good cleaning with some kind of bleach solution and extensive flushing would dislodge things and leave the tank cleaner.

Again, this is what I understand. I hope you find the right solution, good luck!

Originally Posted by Cubman9000

Hello, New to forum. We have a 2006 Designer 36 RLTS. Sometime when we enter rig we have a sewer oder. Not all the time. It doesn't make any difference if tanks are full, half empty or empty. I'm thinking the vent under the sink not working correctly? Any thoughts as what to look for?

[pop up pilot]

I checked the sink, and it goes straight out to the port under the pup. The shower has a trap before going in to the grey water tank. I put water in the trap and the odor was gone. I have only had this pup for a few months, and thought I had done all the necessary maintenance before putting it away for the winter. The previous owner, unknown to me and much to my chagrin, sold me the pup with a full cassette in the toilet. On the three hour trip home, the cassette leaked. It took me days to clean all of that mess out. I feared that the cassette mess had escaped the outer vault/housing/whatever it is called. Fortunately, and thanks to advice in this forum, I was able to isolate the problem to the trap and grey water tank. In the spring, when I take this out of storage, I will do a thorough cleaning of the grey water tank. For the moment, keeping the trap wet will contain the odor. Thanks to all the contributors for your advice.

[360Bridges]

Perhaps a dead mouse or other rodent?