Thetford discontinues the recirculating toilet

[Bill]

I just had a phone conversation with Paul Wipf, the CEO of Trail Manor Industries. He tells me that Thetford has discontinued making the recirculating toilet used in the Trail Manor. Although a few of our members have heard this rumor, Thetford has still not publicly announced it - they have simply stranded their customers. Thetford has no stock of these toilets, and TM has only a few in their factory inventory.

So where does this leave Trailmanor Industries?

Paul would like to switch to the Dometic Sealand M-28, and he sought RVIA approval to do this. However, RVIA refused. The current RVIA code requires that anything with a black water tank must be vented through the roof. Sidewall venting, or through-floor venting, is not allowed. There is apparently no realistic appeal or variance process for this requirement. So when the factory exhausts its limited stock, all Trail Manors will be built with the currently-optional cassette toilet.

And where does it leave Trail Manor’s owners and buyers?

You can no longer buy a Thetford toilet, or any parts, through Trail Manor. Their stock on hand will be used for new builds until they run out, which will be soon.

My personal thoughts are these:
1. If you need parts for your Thetford recirculating toilet, find them and buy them now. RV parts places, physical or on-line, may still have a few parts in stock, but once they are gone, there will be no more.
2. If you are planning to buy a new TM soon, and you want the Thetford toilet, order it now, put down a reasonable deposit, and specify in the purchase contract that it must have the Thetford toilet.
3. The RVIA is an industry group. It sets standards for RV manufacturers, but it has no jurisdiction over owner changes or upgrades. You could buy a new Trail Manor with no toilet at all. Once you take delivery, you would be free to install an M-28 or other toilet of your choice. A number of Forum members have done this.

Sorry to announce this, but it is apparently true. We would welcome any potentially helpful thoughts.

Bill

[ShrimpBurrito]

Thanks for the update, Bill. I can't say as I'm surprised. I think the Electra-Magic has a very small customer base, and TM was probably the biggest customer in the U.S. by far, and that's not saying much.

Where to go from here for TM is indeed challenging. Sure, the cassette toilet is a sure-fire way to continue in the TM lineup, but since there are a number of TM customers that prefer to dump everything at the dump station, and they don't want to reinstall a Sealand after buying a new TM, this could be a significant problem for them.

Sure, they could put in a "slinky" hose of sorts going from the toilet to the roof as a vent that would in turn collapse when the roof is folded, but that's not ideal. Plus then there's this slinky hose along the wall in the already small (relatively) bathroom.

Two immediate ideas come to mind:

1) they can make their own recirculating toilet from the ground up. Sure, there are some significant up-front costs to get that started, but it's a simple device. And frankly, there are numerous ways in which the Electra-Magic could be improved, starting with a stronger top on which the seat rests. And with 3D printing now readily available to anyone, building prototypes would be cheap and easy. They could also ask Therford if they'd be willing to sell their molds.

2) They could install a Sealand toilet with the ball flush valve removed, essentially creating a vent just like the Electra-Magic. Maybe put in some sort of flap that covers most of the hole, basically a better version of the vinyl skirt, obscuring the contents of the waste tank and also preventing waste from sloshing up into the bowl while traveling, but leaving part of the hole open to vent. It could be small....1/4", 1/2", etc. Again, with 3D printing, it would be cheap and easy to try various designs.

Dave

[Shane826]

The solution is simple. Send the trailers out to the dealers “toilet ready” and have the toilet be a dealer installed accessory. That SeaLand is so simple to install. Car companies do this all the time. For example the Dodge Demon… You get a monster muscle car for $85k. It fits into Dodge’s EPA fleet numbers. But for $1 you get a retuned ECM, race front tires, high flow air filter, and tools to install it all. Add race fuel and you have an 800hp BEAST that puts down the fastest 1/4 mile time of any production car EVER built.

And not for nothing but what does the RVIA really entail? It sure doesn’t cover quality control issues, based on what I’ve read about the RV industry in general (not calling out TM here)…

[BaconLover]

I wonder why the RVIA only allows black water tanks to be vented through the roof - is it that gasses can build up and won’t escape through a side or bottom hole? I can’t believe that there’s no way to appeal or ask them to investigate and add a variance to the rules. Someone must be in charge of updating the rules semi-regularly, right?

Oh wait, I might be living in La La Land, so excuse the optimism!

[JohnMD]

I could be wrong, and perhaps there is a plumber who can confirm this. I presume that the rules for RV plumbing would follow the same rationale for buildings. It is my understanding that homes can have wall vents for sewer lines, but that code in most jurisdictions requires the wall vents to be above the highest window. As such, I presume the concern for TM is that a wall vent would be below the windows with the possibility of gases working their way back into an open window. Here is my idea:

TM installs wall vents that have an exterior coupler (some sort of screw on or quick connect), to which an 90 degree elbow and vertical length of pipe (or flex pipe like the sewer hoses that can collapse to a shorter length for storage) can be attached during opening. The pipe would run up along the exterior wall allowing the vent to release above the window. There could also be a bracket of some sort mounted to the top of the wall to secure the pipe. Of course, owners who are not worried about the venting and don't want to bother with it can just store this pipe in their basement and cover the wall vent with some sort of screening, right? But, I think my idea and a disclaimer about its importance in the manual would give TM a way to be in compliance with regulations.

Thoughts?

John

[rickst29]

that RVIA has no problem with stinky generator exhaust, belched out underneath many Trailers and RV's which have exhaust pipes WHICH DO NOT GO OUT ABOVE THE ROOF.

[Bill]

Originally Posted by JohnMD

I presume that the rules for RV plumbing would follow the same rationale for buildings.... It is my understanding that homes can have wall vents for sewer lines, but that code in most jurisdictions requires the wall vents to be above the highest window.

You are partially right. For reasons that are unknown to me, most building codes, including residential building codes, a lot of industrial building codes, and RV codes, are written and maintained by the NFPA (National Fire Protection Association). Minor mods such as the words "recreation vehicles" are inserted into the text to make it application-specific.

I checked out the NFPA, found the RVIA code (called Standard 1192), took a look at the Plumbing section (Chapter 7) and specifically the paragraphs on Venting (sub-chapter 7.6). Much of it is basically identical to the Residential Building codes. As you surmised, sidewall venting is allowed in certain cases (which the TM meets), but with the attached requirement that the vent be "as high as practicable and not less than 6 feet from the ground level." No mention of window height. For TM, the 6-foot requirement would be a problem, since the top of the base shell of the trailer is not that high.

As such, I presume the concern for TM is that a wall vent would be below the windows with the possibility of gases working their way back into an open window.

No rationale for the requirement is given - presumably because if a rationale were given, it could form the basis for an exception request. And the NFPA is a huge, ponderous organization that doesn't want to be bothered with a slew of special requests.

Your idea for an owner-installed vent pipe will almost certainly not fly. I forwarded Shane's thought about "toilet ready construction" to Paul Wipf at the factory, he contacted RVIA, and was immediately turned down. Although Paul didn't forward the specific words of the refusal, it was clear that the trailer must be originally built with a vented system. You can't rely on installation of a vent as part of the setup procedure.

I pointed out one thing to Paul. Hi-Lo trailers have a conventional toilet and a black tank. Presumably Hi-Los have RVIA certification (although they are presently not building trailers due to Covid). I don't think a Hi-Lo base wall is 6 feet high. I suggested Paul get together with his counterpart at Hi-Lo and discuss it. I don't know how Paul will proceed.

Bill

[Bill]

Originally Posted by rickst29

that RVIA has no problem with stinky generator exhaust, belched out underneath many Trailers and RV's which have exhaust pipes WHICH DO NOT GO OUT ABOVE THE ROOF.

You are apparently right. Standard 1192 Section 6.4.3 covers generator installation, and has only a few minor requirements. Exhaust height is not one of them, although a WARNING sticker is required.

Bill

[ShrimpBurrito]

A vent pipe to the roof in a Hi-Lo would probably much easier vs. in a TM, since it could be a hard telescoping pipe.

And of course, whatever solution they do come up with, particularly if it is some odd contraption that vents to the roof, the solution has to be acceptable to potential buyers. You don't want it to tank sales. Imagine the sales demo where they show you how to connect the vent to the poop tank? After all, they do already have an acceptable solution to many people, that being a cassette toilet.

A small diameter version of a sewer slinky hose might be an option, particularly if it was hidden or disguised if inside. Stretched tight, it would be straight and less unsightly. If outside, I wonder if it could it be run up the shell support arm, much like the wires for the A/C, lights, TV antenna, etc.? That might be be workable particularly if they used a traditional black tank mounted under the trailer instead of the Sealand toilet. I know there's not much room under the trailer though.....

I wonder also if they could run a vent pipe up inside the wall of the base shell with a flange or coupler at the top of the base shell that would join a similar flange at the bottom of the rear shell when the rear shell is raised. Another pipe would be inside the wall of the rear shell, which then vents out the top of the wall before it hits the roof (which would meet the 6-foot requirement). Two elbows would be required where the top and base shells meet to do this, and some foam seals on the meeting flanges could make for an adequate seal for such a low pressure connection. Even a magnet seal could work -- there are magnet seals used in dryer vents, which is a much higher pressure application (https://www.magvent-dryervent.com/). Some sort of snap locks could also be used at the seal to make a pressure fit once the shell is raised, though the risk there is that an owner would forget to release it before putting the shell down, and cause significant damage.

Dave

[ShrimpBurrito]

The more I think about this, the more I like the idea of the vent pipe in the wall. Enter the wall of the bottom shell from the Sealand tank, then up the wall and exit to a flange on the exterior wall just below the top of the wall. That flange can then mate with another flange attached to an elbow protruding slightly below the bottom of the top shell. When the shell is raised, the connection is made. When the shell is closed, the flange in bottom shell is flush with the wall, and therefore does not interfere with the shells closing, and the flange coming out of the top shell simply protrudes maybe 2 inches below the bottom edge of the top shell, and so won’t cause any issues with road clearance.

It requires zero additional setup by the owner, should be robust, and should also provide a good seal when the flanges mate. Curious to hear what others think.

Dave