Venting composting toilet on A25

[patclem]

So, after 8 weeks my composting toilet finally arrived. Messing around with the configuration before installing, I'm kinda torn over where to vent it. Here are my options:
1. Go up straight through the roof. I don't really like this, but I guess I could if I have to. The teak handles are kind of in the way of the ideal spot.
2. Run vent hose aft and out the starboard holes that were already there for a diesel heater that has been removed previously. I plan to install an Airtronic heater, so it might conflict with that install.
3. Vent through the hull, probably under the window-ish below the rub rail. This will require a hole, and I need to install a clam shell over it.
4. Just vent it into the cockpit. This wouldn't be great if we had the enclosure in place, but it might work most of the year.

Anyone already do this and have some feedback on what they did?

[motthediesel]

Well, we have an A27, and we’re fitting a C-Head composting head in our boat. My plan is to vent the hose into the engine room with a charcoal filter on the end. Those filters are intended for use in the venting of home “grow rooms” without the tell-tale smell.

I think it will work just as well in this application, we’ll see I guess

We have a “Nature’s Head” composting toilet in our old Avion camper — we love it and we’ll never go back to a holding tank unit.

[Dieselram94]

Is my understanding correct that composting toilets require a separate disposal of liquid? I assume if that’s correct that it’s not exactly a pleasant task?

Well, we have an A27, and we’re fitting a C-Head composting head in our boat. My plan is to vent the hose into the engine room with a charcoal filter on the end. Those filters are intended for use in the venting of home “grow rooms” without the tell-tale smell.

I think it will work just as well in this application, we’ll see I guess

We have a “Nature’s Head” composting toilet in our old Avion camper — we love it and we’ll never go back to a holding tank unit.

[motthediesel]

No, I suppose it’s not “pleasant” — but compared to pumping out with the “stinky slinky” hose, or (worse yet) dumping out a Porta-Potty — it’s a walk through the tulips

It’s also dead simple — never anything to clog or break — and no smell — ever.

Yes, we have become two more of those annoying composting head disciples — sorry!

[Bob Noodat]

Is my understanding correct that composting toilets require a separate disposal of liquid? I assume if that’s correct that it’s not exactly a pleasant task?

Yes. Usually a milk jug! Try to stop spillage with that in a small boat.

Also, composting toilets in boats are an oxymoron. Composting takes a certain amount of time, measured in weeks or months. There is not enough time in the weekly or bi-weekly emptying most units will see. You are emptying the equivalent of a cat litter tray, with unprocessed and therefore unsterilised human turds/diarrhea, into somebody else's garbage or burying it shallowly where you hope someone or someone's pet dog won't discover it. The most responsible thing to do is to empty the bag or bucket at a dump station. Well, why not buy a cheap portaloo, pee in a milk jug, and empty the solids from the portaloo at a dump station anyway!

Another Feelgood Fad.

[motthediesel]

Of course, they don’t really “compost” — that’s very true. What they do with the number 2 is coat and dry it so that it doesn’t smell. And as far as it’s health effects on the trash stream, how is it any different from diapers, both infant and adult? Not to mention all those little bags of dog-doo. I would argue that it is less offensive than either of those due to it’s partial desiccation.

I’ve worked my whole life in property management, with a “concentration” in plumbing — so I dare say by now I know my s**t. And so I prefer the flushless heads because I think they’re just better, not because they’re somehow hip or trendy.

Also, removing the head meant we could get rid of that tiny holding tank the A27s came with. In it’s place we fitted a 22 gal fuel day tank. That was a very worthwhile trade in my opinion.

I’ve been around boats and campers since childhood, and I’m never going back to holding tanks.

[Bob Noodat]

I won't argue your points Tom. I think the solution for us is likely to be Scandinavian: the Cinderella incinerating toilet. Expensive but proven in long use. I only have a Canadian link.

https://www.thecabindepot.ca/products/c ... ion-toilet

[nebulatech]

Also, removing the head meant we could get rid of that tiny holding tank the A27s came with. In it’s place we fitted a 22 gal fuel day tank. That was a very worthwhile trade in my opinion.

Your day tank is larger than the A25 main tank!

I'm happy you found a solution that makes your life better! My cousin had the Lectra-san system. I always liked the idea of that system; no holding tank, no mess, no problem with the fish cops. Its my understanding that lectra-san is not longer allowed, but it draws too much power for my A25 anyway.

[DesertAlbin736]

Of course, they don’t really “compost” — that’s very true.

"Desiccating head" might be a more accurate description. Nothing wrong with that. They do require the small very low amperage vent line fan to run 24/7/365. Not a problem with a small solar trickle charger. Urine does need to be separated from solid waste & the two name brand units have diverters to channel the pee pee into a separate removable tank.

[NickScheuer]

I installed a vent immediately aft of the cabin window which extends into the head compartment. The exterior opening is covered by a clamshell hood opening downward to so it sheds rain. Try not to install the vent opening too close to where folks in the cockpit might notice the odor, if any. Our vent location has proven good in that respect.

[motthediesel]

I won't argue your points Tom. I think the solution for us is likely to be Scandinavian: the Cinderella incinerating toilet. Expensive but proven in long use. I only have a Canadian link.

https://www.thecabindepot.ca/products/c ... ion-toilet

That unit may well be a good solution Bob, but at almost 7x the price of our C-Head, it better be

[patclem]

Any time someone mentions composting toilet, it generates a lot of debate. Still not sure where I'm gonna vent it. Maybe I'll just vent it into the cockpit or the aft bilge temporarily.

I'm removing an Electrasan "poop cooking system", which probably works, but is not the chemical one so it's illegal as I understand it. It's definitely more complicated, has huge battery cables to it, and another possibility of failure. We've never used it and neither did PO who had the boat for 3-4 years. If anyone wants it for free, I'm about to pull it out. Come get it near Nashville.

[WillieC]

Peggie Hall recently posted on Cruiser's Forum her suggestion for small boats:

Dometic/SeaLand 975MSD

That is high praise from the queen.

I am not now nor ever have been a member of the above mentioned enterprises.

[nebulatech]

Patclem, we do Thanksgiving in Crossville. If you still have it, I might take you up on it!

[stxray]

I installed a Nature's Head composting toilet on my A25 and was quite pleased.
On my boat there was already a clam shell vent covering the bilge fan exhaust on the starboard side of the hull just below the rub rail. I vented the head just forward of that with its own clamshell cover.

As to performance, I found for one person I could go about 3 weeks before I needed to empty the conifer medium used to process the solids. If there was any oder is was the smell of dirt. The unine bottle needed empting about 7-10 days. It wasn't an unpleasant job. I was never refused permission to pour it into their toilet when stopping at a marina. Given that the container was translucent, it was obvious what I was carrying so, I did feel a little awkward carrying it down the dock. I kept one of those non-woven shopping tote bags in the head and placed the container into that.