Nature's Head and Venting

[MBLittle]

We've decided to rip out the smelly old jabsco and holding tank in favor of a composting head. So a question about venting unique to our situation.

I'd rather not drill a new hole in our deck for the vent tube, so I'm wondering if I can use the old pump out hole. Problem is it's about 10' back and 4' vertical from where the new head would be...

Would a basic solar vent be enough to pull that distance? I was thinking I might need a 12v computer fan at the head AND the solar vent at the end, but hoping I wont need to wire the fan at the head...

Another concern (from the wife) is the pump out port is in the forward part of the cockpit, so would the smell be noticeable?

[SariTimur]

We did this, about the same dimensions and it worked fine. We mounted the screw down mushroom vent that fetus makes and Natures head modified and it installed over the top of the old pump out fitting so I didn't need to remove it. We just use the existing vent fan no extra solar vent. Regarding the smell the first couple of weeks we noticed a bit of smell in the cockpit until the compost started doing its thing. I was worried that I was going to have to do something drastic. But once the compost started it fixed it. Now we only get smell immediately after use and just before we need to empty. Basically if we have a smell, I come back and check an hour later and if it still smells I look at the calendar, we mark it each time we dump the compost. If it looks to be about the right time I change if not add some cedar chips to the compost.

Cheers

Mark

[SVTatia]

Originally Posted by SariTimur

...We mounted the screw down mushroom vent that fetus makes...

oops!

We've decided to rip out the smelly old jabsco and holding tank in favor of a composting head...

Be careful and think this thru, you don't want to replace a smelly cabin with a smelly outside... A hole in the deck with a well installed mushroom vent should pose no problem. Just saying.

[SariTimur]

Damn spell check. That was Vetus makes. Anyway there is no smell after the process starts to cook. Just that first couple of days. Interesting we got bugs once so I stripped apart everything and cleaned it. So should have smelled when we restarted the concoction, but we didn't get it. Maybe that first couple of days we were eating something bad! Anyway we have had ours for almost two years and wouldn't go back. This subject has been on numerous posts. I just wanted to let the OP know our vent is just forward of cockpit and no issue with the same size hose runs.

[Mike OReilly]

Our NH setup has approx. a 4' rise (guesstimating), and I use a mushroom vent with the built in mini computer fan as the only air flow. Works fine for that lift. Our run isn't as long though. I suspect it is the lift that will tax the system more than a horizontal run, so I'd wire the NH vent with a simple mushroom on deck, and only go with a solar vent if you found you really need the extra air flow.

Aroma-wise, there should be no fecal smell coming out past perhaps the first couple of minutes after a use. If I get up close and personal with our vent (which I don't do very often) the only odour I smell is that of earthy soil. I have to have my nose right up to the vent to get even that. Any lingering odours indicate there is something wrong with the mix, or as SariTimur says, it's time to empty the bin.

[Mark Hall]

You might want to consider the C-head. It seems to be a good solution and doesn't require a direct vent. You could still use the existing hole to just exhaust air. I have the Airhead, which works very similarly to the Nature's Head, but I am thinking of switching over to the C-head for longer term cruising.

[valhalla360]

As long as there are no sags to trap water, I doubt the length will be an issue. It mostly just needs a fresh air supply. It doesn't need hurricane force wind blowing thru.


We removed the pump out and put in a solar vent but ours sits directly behind the toilet. I've never got up close and personal with it while someone is using the head.

[Cthoops]

The vent for our Nature's Head is well over 10' away from the head itself. Probably around 18'. We placed a Vetus mushroom vent over where the old pump out was, and we haven't had any problems with the placement.

I sing the praises of our Nature's Head to anyone who will listen. When we buy our next boat (for full-time cruising), our first project will be to tear out the head and replace it with the Nature's Head.

[Canibul]

I still have to repress a slight shudder when I remember that day last year that I discovered that the 30 year old stainless welds on our 30 gallon stainless holding tank were brittle and broke off, with the tank half full of a previous owners leavings. I started that job trying to find the source of the smell in that hull. Before the day was out I had ripped out the holding tank, the Baby Blake marine head, and all the hoses. My better half is a member of a Women Who Sail group and she started telling me about the NH experiences she was reading about. I installed the first one then. Six months later I removed the other Baby Blake and installed a second Nature's Head. Both are vented using the Nicro solar vents. I 3D printed an adapter for the 1.25 " hose.

I never want to share my living space with another tank of offal. I'm thinking of installing a third one in the RV. Anybody know where I can sell a couple of Baby Blake marine heads with a bunch of spares?

I'm curious about the questions on rise and hose length. Surely you don't think ambient air is the same as pumping water, do you? I don't think it makes any difference how high or how far away the outlet is. Whatever fan you use will move the air. Put it a hundred feet away, and a hundred feet up, and I suspect the little 12 volt muffin fan will work just fine. This has no relationship to hydraulics.

[valhalla360]

Originally Posted by Canibul

I'm curious about the questions on rise and hose length. Surely you don't think ambient air is the same as pumping water, do you? I don't think it makes any difference how high or how far away the outlet is. Whatever fan you use will move the air. Put it a hundred feet away, and a hundred feet up, and I suspect the little 12 volt muffin fan will work just fine. This has no relationship to hydraulics.

Actually it's fluid dynamics and does have a relationship but the losses are small and the needed air flow is also small, so shouldn't be an issue. As long as there is some airflow, it will work fine.

[winjamerk]

I had an AirHead on my 40' and there was a deck vent box with cowl near the top middle of the box above the head. My AirHead had a 1-1/2' vent tube. I made a new hole in the ceiling and another hole in the box top aft of the cowl. I snaked the vent hose straight up from the AirHead thru the new hole. There was a small internal exhaust fan that drew air thru the composting chamber and out the tube. I covered the new box hole with a solar vent. Seemed to work just fine. Never heard a complaint about odors.

[jkindredpdx]

I was all concerned about venting, but got mid way installed without one and so far don't feel compelled to put any holes in my deck.


JimK

[Scout 30]

Thanks to Mark Hall for recommending the C-Head. I've been thinking about making this change but My head is in the bow so the wall behind it is quite short. Not only does C-Head make a model that will fit but they actually have a picture of a mahogany colored C-head installed in a Scout on their website. Looks like this might be a win win.


http://www.c-head.com/images/dunn2_cr.jpg

[jaybird1111]

Have a C-head, may not be relevant, but I'll try anyway:

Very humid where I am. Condensation etc made for a damp compost situation. I talked to Sandy the C-Head proprietor, but before I had a chance to get around to fabricating up what he advised, in the meantime I just left the lids up while not in use.

That has worked, so I've not done any vent system.

[Scout 30]

I'm in Florida so humidity is also a problem here. Sounds like you're saying a vent would solve that problem? Also, didn't you get a strong odor from leaving the lid up?