Powered Vent for Thetford Recirculating Toilet - Page 3

**Larryjb** · 06-27-2020, 03:32 PM

I was looking at this again. I noticed that the bathroom wall had to be removed to gain access to the vent under the sink. Now, it's only a thought, but what about just making a simple vent out the back right behind the toilet?

Pros: easier to plumb.

Cons: fan assembly and wiring is visible, requires a new hole through the side of the trailer.

**rickst29** · 06-27-2020, 04:22 PM

Sliding the kitchen-side bathroom wall outwards and into the hallway (as far as it would go) gave me enough access to the DWV pipe (to insert my "T" fitting). But my "T" was undersized, compared to the superior and original implementation.

**Larryjb** · 06-27-2020, 04:44 PM

Quote:

Originally Posted by rickst29

Sliding the kitchen-side bathroom wall outwards and into the hallway (as far as it would go) gave me enough access to the DWV pipe (to insert my "T" fitting). But my "T" was undersized, compared to the superior and original implementation.

Thanks, that's good to know, that should simplify installation.

**Larryjb** · 06-27-2020, 07:43 PM

For those of you reading this, a consideration that has not been discussed is the choice of fan. You can commonly get sleeve or ball bearing fans.

Flyboy's set up with a flexible hose has the benefit of being able to swap the fan out fairly easily if it fails. According to the following site: https://www.nmbtc.com/white-papers/b...g-performance/ , ball bearing fans will outlast sleeve bearing fans by around 18-44% when used in temperature ranges from 25 to 40°C. Given that the fan will likely be used when the trailer is occupied, one is probably not going to be living in 40° trailer, so one could expect a modest 15-20% better lifetime over the sleeve bearing.

Another consideration is the orientation of the fan. If it is mounted horizontally as Flyboy's fan is, the ball bearing fan will outlast a sleeve type fan.

Of course, one has to wonder just how much it really matters. How many hours will you be running this fan? Suppose you vacation for 3 weeks in the year. The fan would be running a maximum of 500 hours a year. A sleeve bearing fan running at 50°C has an expected lifetime of 40000 hours. At 500 hours per year for a 3 week trip, the sleeve fan should be expected to last around 79.36508 years. (a little tongue in cheek, but you get the point).

The last question I don't see answered is how the fan will fare in damp cold winters in and around the 49th parallel. The ball bearing fan is well sealed in general and probably will fare better.

The bottom line seems to be that as long as you install the fan in a fairly easily accessible location and can change it out, it probably doesn't matter what style fan you install. But for me, living in this cool damp winter climate, I will probably opt for a ball bearing fan.

FlyboyTR · 06-28-2020, 05:51 AM

Quote:

Originally Posted by Larryjb

I was looking at this again. I noticed that the bathroom wall had to be removed to gain access to the vent under the sink. Now, it's only a thought, but what about just making a simple vent out the back right behind the toilet?

Pros: easier to plumb.

Cons: fan assembly and wiring is visible, requires a new hole through the side of the trailer.

Larry & Rick,
I completely removed the sliding bathroom wall. That is a two person job to safely remove and reinstall it. I removed it solo...and would not attempt that again! LOL For me, removing the wall was the better option and allowed me easier access. Yep, the flexible hose was a winner!

I had considered exiting the vent through the camper side wall from inside the vanity. That would have saved the plumbing/access issues involved in getting to the existing vent pipe. Working under the vanity is tight (without removing the lavatory or entire top). Even with exiting there, I think the flexible bilge hose would be your best friend! That said...installing a new wall vent exit under the vanity is a very viable option. I had looked at bulkhead fittings similar to this: https://www.amazon.com/Lifegard-Aqua...3344285&sr=8-3 .

For the outside cover I would use the Valterra louver (same as OEM for the vent pipe): https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

The good thing is that there are several viable options for the powered vent installation. But regardless of how one may configure it, I believe it should always be EASY to service for fan replacement, maintenance or upgrades!

In regards to ball bearing vs sleeved...I agree that ball bearing would be the better option even though I the fan (x2) I used was the sleeve type.

Good stuff...

**Larryjb** · 02-21-2021, 02:36 PM

I'm not sure if this might be a useful "modification" to the powered vent system. If you are concerned that the powered vent might be smelly to the neighbours, hook up a vent hose to the sewer connection. This could be easily accomplished by connecting to one of those cleanout style elbows. Just a thought.

This is probably not necessary, but I thought I'd put it out there anyway.

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.

**Larryjb** · 02-26-2021, 08:39 AM

Quote:

Originally Posted by Larryjb

I'm not sure if this might be a useful "modification" to the powered vent system. If you are concerned that the powered vent might be smelly to the neighbours, hook up a vent hose to the sewer connection. This could be easily accomplished by connecting to one of those cleanout style elbows. Just a thought.

This is probably not necessary, but I thought I'd put it out there anyway.

Off-board, Bill mentioned to me something I hadn't thought about, and that is the possibility of a P-trap on the campground side of the sewer. If a P-trap exists in the campground sewer, a fan is not going to work, and worse yet, will end up blowing out the water in your sink P-trap, blowing all the glorious odors into your sink.

I'm not sure if a P-trap exists at the campground sewer or not. If one exists, there must be a vent elsewhere in the campground for such a trap to work. As long as the the sewer is connected to a trailer, or is capped, there would be no need for a P-trap. So, I don't know. Maybe some campgrounds are plumbed with P-traps, others not.

At this point, my idea is probably not a good one after all, and not really necessary anyway.

So, I would still recommend connecting the vent into the TM plumbing vent system. It's not hard to do. The hardest part will be finding a suitable fan that can be carved to the right shape, and is small enough to fit into a piece of ABS.

**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