Best black tank vent replacement?

[Pahaska]

I'm surprised that you still have an odor problem. I installed the same Dometic 310 and have no problems. My AI is in the covered storage with temps close to 100 most days here in Austin. Over the last 2 weeks, I have been at the storage for a couple of hours at least every other day and used the facilities most times, both ways. I'll empty and flush the tanks next time I bring it home.

Even under these conditions, I have no detectable odors. I was just there this morning.

[Alex AVI]

Originally Posted by Boxster1971

IB - you are getting a lot of replies to your question that are mostly noise. FYI - Airstream used the 360 Siphon vent on my Interstate. I think they are standard vents used by Airstream since about 2010. The 360 Siphon is a good quality tank vent that has worked well for me in last six years.

+2 on my 2018 AI Lounge - 1 for black & 1 for grey. Gray venting routed thru toilet sink on C/S, not galley sink on R/S. No odors even in worse case scenario of 114°F outside and 117°F inside temps. Even when forgot to drop black tank treatment, very, very minimal issue with odor. With black tank vent directly behind the toilet and bathroom power vent only few inche next to it, obviously you do not want to turn on bath power vent when toilet flapper is open. Coz that switches flow of venting, instead of going up the 360 Siphon, it is sucked nicely back out through bowl, through you nose, into bath before exiting bath power vent.

[InterBlog]

Originally Posted by Pahaska

I'm surprised that you still have an odor problem. I installed the same Dometic 310 and have no problems. ....

You may already have the vent that Mike mentioned, given your MY. You have the $20 version. I have the $5 version.

Edit: The reason I started examining the 360 as an option is because of the white paper that Mike linked to the Learning Curve Pointers thread. I'd seen that paper before, but not read it through, because it is 63 pages long. In there is the following statement:

"For example, a 360 Siphon is an effective $10 part that can eliminate RV odors, which people who actually use RVs know is a consistent problem. But, many manufacturers won’t install the simple device. Why? It will push them out of the mythical price point."

[Titus]

If your flush plate is working (i.e. water stays on top of it long after it is flushed), I don't under stand how there can be odors from the black tank other than the brief time the plate is open while flushing. Seems that when the plate is open any vent is going to be smaller than the flush opening so odors will filter up into the bathroom. It would take a very powerful van on the vent line to keep the air flow going into the tank while flushing.
Our grey water waste lines have the HEPVO traps, which do an adequate job of keeping the grey tank odor out of the MH.
We have not noticed any significant odor in the MH, so whatever Airstream has installed for tank vents, they seem adequate to me. In short, we do not seem to have a problem that needs to be solved with something fancier than what is there now.

[Tincampers]

Originally Posted by Titus

If your flush plate is working (i.e. water stays on top of it long after it is flushed), I don't under stand how there can be odors from the black tank other than the brief time the plate is open while flushing. Seems that when the plate is open any vent is going to be smaller than the flush opening so odors will filter up into the bathroom. It would take a very powerful van on the vent line to keep the air flow going into the tank while flushing.
Our grey water waste lines have the HEPVO traps, which do an adequate job of keeping the grey tank odor out of the MH.
We have not noticed any significant odor in the MH, so whatever Airstream has installed for tank vents, they seem adequate to me. In short, we do not seem to have a problem that needs to be solved with something fancier than what is there now.

Ditto, ours works quite well.

[InterBlog]

Originally Posted by Titus

If your flush plate is working (i.e. water stays on top of it long after it is flushed), I don't under stand how there can be odors from the black tank other than the brief time the plate is open while flushing. ....

Easy answer, and covered in this other thread here - the toilet itself is not air tight because of the way it is seamed together. There's an interstitial space between the inner bowl and the outer base. Even if the attachment flange is sealed correctly, odors (and in the case of the Thetford, solid waste) creeps up into that interstitial space and then escapes into the wet bath.

We had a lot of people not able to visualize that process on the other thread. Apparently so did popular blogger and DIYer Roadtreklife, so on his blog post here, he actually cut his toilet in half with a saws-all to try to make his point for people.

We never had this issue for the first several years of ownership - it only developed in September of 2017. When it does develop, it's not going away without a proper fix.

[gmillerok1]

After I replaced the stock toilet with the Dometic 310, it was like night and day (or maybe stinky and not stinky). I carefully sealed the area around the base with silicone.

One issue with the old toilet was that it was not possible to do that. The base was open at the back, so anything inside got on the inside could (and would) smell outside.

The 310 is sealed all the way to the tank-even when the flap is closed, unlike the other version. If anything slops around, it stays on the other side of the flap.

It is puzzling why anyone would still be having odor problems with a 310/320 Dometic.

[InterBlog]

It's dirty because it's too hot outside to wash the van. We don't just get fire - we get a form of brimstone with it. A lot of that gunk up there is dirt from the Sahara that keeps pulsing ashore here.

Let the testing begin.

[Tincampers]

Originally Posted by InterBlog

It's dirty because it's too hot outside to wash the van. We don't just get fire - we get a form of brimstone with it. A lot of that gunk up there is dirt from the Sahara that keeps pulsing ashore here.

Let the testing begin.

Looks good IB. Come up here, rain predicted for next seven days.

[coolbikeman]

Installed one of these on our previous rv that had black tank vent under the refrigerator vent on the roof. They are getting hard to find. Don't know if the company is no longer making them. It worked great and is lower profile than some of the other swivel vents.

http://rvparts.camperlandok.com/rv-parts/31-8293/Ap-Products/Xtreme-Vent-White-318293

Originally Posted by InterBlog

We have three recently-active toilet threads on this subforum, but this is a different topic altogether: the issue of proper tank venting.

Our model of Airstream Interstate has separate gray and black tanks. The black tank is internal under the street side cabinetry. The gray tank is external, slung under the chassis, more-or-less underneath the black tank.

In an interesting twist of engineering, both tanks were plumbed to the same roof vent line using a Y connector.

We replaced our original nighmarish Thetford toilet with a Dometic late last year after developing major odor problems. You can read about that adventure on this blog post here and this Air Forums thread here.

The replacement job did result in an improvement, but there is still some detectable odor. Dollars to donuts, that has something to do with improper air flow through the whole plumbing system. In other words, we only solved half the issue when we upgraded the potty.

Which brings me round to our rig's nightmarish tank vent installation. You can see that in the image below. For the moment as a stop-gap, I've got that gruesome hack job sealed up with a Fort Knox-style re-caulk application (Sikaflex 221), but it's on my late-2018 DIY cool-weather project list to open up what is sure to be revealed as a major can of worms and replace it with something better.

What is that something better? Has anyone installed a 360 Siphon roof vent on their Interstate? If so, what feedback do you have? Is it worth the trouble and does it do what it claims to do? Or should I be considering other vent products?

Thanks.

[InterBlog]

Originally Posted by coolbikeman

Installed one of these on our previous rv that had black tank vent under the refrigerator vent on the roof. They are getting hard to find. Don't know if the company is no longer making them. It worked great and is lower profile than some of the other swivel vents.

http://rvparts.camperlandok.com/rv-p...t-White-318293

Thanks - I hadn't encountered that option anywhere previously.

[Tbeck11931]

It seems to me you have a vent system leak somewhere, either in the vent pipes itself or near the connection at the tank.

[InterBlog]

Originally Posted by Tbeck11931

It seems to me you have a vent system leak somewhere, either in the vent pipes itself or near the connection at the tank.

We do - and so do many other owners. The toilet itself cannot be made air-tight. We can make the flange air- and water-tight, but not the body of the toilet itself. That's why I'm trying to compensate for that limitation through improved venting.

[Re-Pete]

Originally Posted by InterBlog

We have three recently-active toilet threads on this subforum, but this is a different topic altogether: the issue of proper tank venting.

Our model of Airstream Interstate has separate gray and black tanks. The black tank is internal under the street side cabinetry. The gray tank is external, slung under the chassis, more-or-less underneath the black tank.

In an interesting twist of engineering, both tanks were plumbed to the same roof vent line using a Y connector.

We replaced our original nighmarish Thetford toilet with a Dometic late last year after developing major odor problems. You can read about that adventure on this blog post here and this Air Forums thread here.

The replacement job did result in an improvement, but there is still some detectable odor. Dollars to donuts, that has something to do with improper air flow through the whole plumbing system. In other words, we only solved half the issue when we upgraded the potty...

Not sure if you've thought of this or if it's already been mentioned, but if you frequently hook up to sewage connections in RV parks your odor may be coming from there. I see a a lot of folks connect to the sewage line without putting in an elbow bend in their drain hose so that it can fill with water and block odors backing up from the parks sewage line which then makes it's way back into the RV via drain openings, etc.

[J. Morgan]

Put a half a gallon of Clorox down the toilet, another quart down the sink drain and..... no more odor problem. #JustSayin

[guskmg]

If you have an AirHead Compost toilet you will notice it has rubber gaskets on all opening parts including seat to base and lid to seat. The only opening to the inside of the trailer is the powered vent inlet. The toilet is an amazing convienance and gives you the use of the black tank for additional grey water holding. In my case a total of 76 gals.
guskmg