Powered Vent for Thetford Recirculating Toilet

FlyboyTR · 11-09-2019, 03:01 PM

Howdy...!
I have been off the forum for quite some time. We have been traveling! Before I went dark, I had mentioned a powered vent system I was wanting to build for the stinky Thetford toilet. We tried and tried different things but was never able to keep the odor at bay. Either stinky poo or chemical...or both. Now that I have built and installed this simple vent fan...the stink is gone!

I built the system using a 2" 12 volt electronics fan. I moved the fill/status gauge from the right side over to the left side. I then plumbed into that opening and installed the system.

I used the existing blackwater drain/vent line. It was cut and then removed to the outside. Part of it was cut out to allow a Tee fitting to be installed. It was then reinstalled and inserted into the new Tee. The outside area/vent cover was resealed and a new vent cover installed.

Below is a link to my YouTube video that shows the build. The parts list is there in the description. I hope it is beneficial and helpful to those of you that are searching for a solution but don't want to replace the toilet.

https://youtu.be/lyg_d4Q7gJs

**Larryjb** · 11-09-2019, 04:46 PM

Are you saying this new powered vent you installed did NOT solve the odor issue?

tentcamper · 11-09-2019, 06:17 PM

Congrats it sounds like you have a solution for the toilet smell. I like it, great idea.

FlyboyTR · 11-13-2019, 08:36 AM

Quote:

Originally Posted by Larryjb

Are you saying this new powered vent you installed did NOT solve the odor issue?

Larry,
My OP could be a bit confusing...thanks for pointing that out. YES...the little vent van does great. (before the mod...it was either chemical or stinky poo smell). At some point I may want to add a slightly larger fan in the system.

But, as is, it works fine and does keep the odors from drifting upwards into the bathroom/camper.

**Larryjb** · 11-13-2019, 06:38 PM

I finally found a link to what I had seen for the recirculating toilet:
https://www.thetford.com/wp-content/...3-Vent-Kit.pdf

It's nothing but a vent kit. I had thought of installing an inline fan for it, but you've outdone it!

I've seen so many abandon the recirculating toilet because of the smell. I knew something like this could work, and you've proven it. This will likely be my summer project for next year.

Now, to prevent clogs. That is a topic from a different thread.

FlyboyTR · 11-14-2019, 04:27 AM

Thanks. Glad the video mod has been beneficial.

Someone PM'ed me and asked why I didn't "just" exit the sidewall under the lavatory. The answer would be ease of access. Working under the lavatory is next to impossible (for me). As is, there is reasonable access for everything I needed to do. Using the flexible bilge hose allows me to easily remove one screw from the elbow on the toilet, reach under the lavatory with one hand and pull the business end out to where it can be serviced.

**Larryjb** · 11-15-2019, 04:19 PM

The other related item I was trying to remember is called the Lil Stanker. It is a fan designed for this purpose and uses very little current. Unfortunately, it seems to be unavailable now.

If you're interested, I came across this long thread and will be pursuing some other refinements. The vinyl flap replacement for the Thetford vinyl skirt will be a good start for me.

https://www.trailmanorowners.com/for...ead.php?t=8112

Bill, you said once that you tried cutting the Thetford skirt and it made no difference. I am thinking of trying the same, but cutting it in 1" wide strips. I may just go directly to ShrimpBurrito's solution and ziptie a vinyl flap.

us.beach.girl50 · 02-26-2021, 06:19 AM

Quote:

Originally Posted by FlyboyTR

Howdy...!
I have been off the forum for quite some time. We have been traveling! Before I went dark, I had mentioned a powered vent system I was wanting to build for the stinky Thetford toilet. We tried and tried different things but was never able to keep the odor at bay. Either stinky poo or chemical...or both. Now that I have built and installed this simple vent fan...the stink is gone!

I built the system using a 2" 12 volt electronics fan. I moved the fill/status gauge from the right side over to the left side. I then plumbed into that opening and installed the system.

I used the existing blackwater drain/vent line. It was cut and then removed to the outside. Part of it was cut out to allow a Tee fitting to be installed. It was then reinstalled and inserted into the new Tee. The outside area/vent cover was resealed and a new vent cover installed.

Below is a link to my YouTube video that shows the build. The parts list is there in the description. I hope it is beneficial and helpful to those of you that are searching for a solution but don't want to replace the toilet.

https://youtu.be/lyg_d4Q7gJs

I haven't bought my TM yet and I'm trying to learn all I can while looking. Is there a factory installed fan? Where does the toilet vent? It sounds like the side wall, not the ceiling. In my 5wer I put this on the vent pipe and it did great. But it sounds like it's not doable for this. https://www.amazon.com/dp/B004UQV3II..._cRQY6U4itu8NS

Sent from my SM-G781U using Tapatalk

**Larryjb** · 02-26-2021, 08:32 AM

There are several work arounds for this. Some installed the vent through the side, then placed an extension tube to vent closer to the ceiling. Other's (like Flyboy), plumbed the vent directly to the drain vent. The TM fan is s simple fan that operates similar to your bathroom fan.

Venting through the side is certainly a very viable solution. I'm not so sure that the extension tube is a necessary modification because the factory fan actually vents to underneath the trailer.

The fan Flyboy used was plumbed into the plumbing vent system so that he didn't have to cut any new holes in the side of the trailer. Also, by venting underneath the trailer (where the plumbing vent is), any smells will have dissipated by the time the get away from the trailer.

Personally, I don't think I'd bother with the solar vent you linked. You could install it into the ceiling and then connect a flexible hose between the toilet and the fan and that would work just fine. That would mean one more setup procedure when setting up camp. Just remember to plug the vent hole at the toilet or you may end up with a very smelly trailer next time.

Any new holes in the ceiling mean new possible water leak sources. Some of these leaks are difficult to spot visually. (I've been there a few times with my TM. I found the only way to guarantee a leak free roof is to remove the vents on the roof and redo the seals underneath the lips, and place sealant in the screw holes. Sealing over top is next to useless.)

This solar powered vent is a very expensive way to do the job. A simple fan like what Flyboy used is much cheaper and uses very little power. You're not going to drain the battery quickly with his fan.

But, you could make your fan work if you like. It is an interesting idea, and would certainly be doable.

**Bill** · 02-26-2021, 08:42 AM

There is a factory-installed vent fan for the whole bathroom. It vents into the space under the tub, where there is a screened exit through the floor. There is no specific toilet vent fan - putting one in place is the subject of this thread.

In most RVs, the (rigid) vent pipe goes straight up and exits through the roof. That doesn't work in a TM because the roof goes up and down. Another choice is to vent through a new opening in the sidewall of the bathroom, as you noted. The Amazon fan that you noted would work as a through-the-roof whole-bathroom vent fan, but that duplicates the fan that is already in place. It would probably not work as a sidewall vent fan because it is too thick. It couldn't be mounted on the outside of the sidewall because the upper shell couldn't slide down over it when the camper is closed. And it wouldn't work inside the trailer because I'm not sure how you would attach a hose or pipe to it.

Travis' idea of connecting a toilet-specific vent fan directly into the plumbing vent seems a good one.

Bill