Sanity check my plumbing plan?

[reepicheep]

I have no idea what I'm doing. This sketch has no relationship to the laws of physics or the placement of items in the house. Assume that all taps will be be at least 3 feet below the top of the rain water tank, if not lower. I don't have a lot of naturally occurring higher terrain to work with, unfortunately.

The water heater tank is likely to be outside of the house, because I'm worried about it exploding. It will be pretty small, around 20 gallons. Ideally, I'd like to have something I can also heat with propane, but I'm not sure if something like that exists and will be compatible with all the other shit I want to do with it. Might just need a big empty metal ammo can I can drill holes in, and forgo the propane. I'd take a few cold showers every year, I imagine.

I'd consider adding a propane fueled tankless hot water heater as well to the whole set-up. I'd just like to avoid being completely dependent on propane for my hot water needs.

https://photos.app.goo.gl/E6LG7HiuhpgrfcVNA

https://www.homebiogas.com/

See toilet option.

https://www.berkeyfilters.com/

All water coming out of taps will be grey water. I will manually fill berkey. That doesn't mean I might not need some kind of filtration somewhere along the line -- at least filtration of large particles coming off the roof.

https://cdn.shopify.com/s/files/1/0100/ ... 0.pdf?4483

This is the wood stove I bought.

https://www.youtube.com/watch?v=nC_Ql5qVs4Q

We have a bigger version of this here and it's pretty rad.

https://www.metalraintanks.com/stainles ... rices.html

Big one, raised up a little. Would love to keep the whole system gravity fed, but it might need a pump somewhere.

[reepicheep]

Thoughts:

This is an iterative process -- I'll probably start out with the simplest options and upgrade as I go, but when it comes to putting pipe in the walls in preparation for later upgrades...I kinda gotta figure that out first. I do know where I'm going to park, at least for the next few years (most likely).

I'll have the option to hook up to shore power and well-pumped water and am going to include electric and plumbing that can take advantage of those things, for sure, if for no other reason than it might be nice to go stay in a different place occasionally (that does make the bathroom trickier though...I guess I could hook up a portable black water tank, probably).

We have a large solar heated outdoor shower here and it works just fine during the vast majority of the summer. It'll even stay hot over night, if the sun was really good the day before. I use it frequently.

The fire-powered heating goes in as an attachment to a woodstove, not an outside campfire like dude in that video had. I've had experience with systems like this as well and they don't take that long to heat up, even with tanks much larger than what I'm imagining. As the woodstove is my only source of winter heating...I imagine I'll be motivated to start a fire for other reasons.

I think incorporating an on-demand propane hot water heater to begin with, but planning out the pipes for this other stuff, might be the way to go. Let's me have hot water while I'm working on the other stuff.

Headspace is going to be tricky. Almost certainly going to need a pump...unless I build a hill, or something. Unfortunate.

[Alphaville]

repicheep, friend,

i don’t know you much but i encourage you to not put a heating tank “outside” without a constant winter power supply you’re willing to pay for in perpetuity, plus sufficient insulation to minimize your costs.

if you want really low maintenance you can always give yourself what my wife calls a “hooker bath” with a simple pot of hot water plus a sponge.

if you want hot soaks then heat a tub and soak yourself accordingly.

a water heater means perpetually ready hot water on-demand and different always-on logicstics.

you can enjoy the pleasures of hot water without the tight coupling with steady & constant energy. unless you want to pay for a a power line. $$$.

i have not looked at every schematic but are you gonna have a rocket mass heater or no?

[reepicheep]

@Alphaville! Your concerns are registered! On demand propane is by definition at least half-way outside. But there's no tank to try to keep insulated.

The other tank I am imaging would be inside a greenhouse and insulated to some degree. It would not be supplied by anything on-grid so it would not be warm all the time, presumably. The solar water heater we use here is not connected during the winter, we drain the lines.

A hooker bath might be the way to go for awhile.

No rocket mass heater. They are cool but very fuel intensive. I went with a traditional wood-stove/oven, somewhat oversized for my tiny space. I will likely be too warm sometimes. I'm ok with this and prefer it to the alternative.

[reepicheep]

@bigato, if you don't need it, I say don't go for it. Study up on Wim Hof instead.

[Alphaville]

i thought the point of a rocket mass heater was low fuel consumption verging on e=mc^2?

i’ve only had cheapo wood stoves and still required fair amounts of firewood chopping + seasoning + splitting. i was pinning my hopes on a rocket stove in old age, because a handful of brambles was suppose to cut it. or so the myth goes.

is it lies? if so, please confirm.

[theanimal]

Why dont you use an on demand propane heater? It's small and you don't have to worry about heating tanks.

My understanding of rocket stoves is that they are much less fuel intensive, but I have not used one.

Edit: Sorry, just saw the on demand tank was already mentioned. What do you mean by "by definition its halfway outside"? Are you referring to the propane tank? Otherwise the propane heater and everything else would be inside.

[reepicheep]

There are versions of on-demand propane tank heaters that are supposed to be outside the house. My neighbor has one in a shed attached to the house, on the tongue of her rig. That might be my plan, though it's the exact opposite side of the house from all of my plumbing needs.

I've seen the heaters inside, too, but yes, the propane needs to go outside.

My experiences with rocket mass heaters are that they don't require *much* fuel, but that they do require *constant* fuel if you want to keep a fire going. You can definitely use them to burn twigs, they do burn hot and are high efficiency. If you're trying to just cook on one, go for it. If you're trying to heat a building, you'll need thermal mass of some kind -- cobb benches and the like -- and that's pretty much the only way I'd consider doing one. But then when you imagine doing that in a tiny house, the weight just goes way way up, and you can surround a wood stove in soap stone with a lot less effort. Also, insurance companies not big fans of rocket mass heaters. Or DIY anything, really.

[reepicheep]

Lol bigato!

I'm right there with you. Hot water is a luxury...but it's one I want.

[reepicheep]

Ok, so.

I want to stick a hot water heater on the storage loft above my wood stove. The wood stove unit I have is designed to heat water -- it comes with a water boiler (the Nectre 350W, for those curious). I'm supposed to open-vent whatever water heater I use with this stove. I'll probably cut a hole in the wall.

This water heater isn't going to be connected to electric or propane. I did buy an on-demand propane hot water heater which will be installed on the outside of the house immediately on the other side of my shower. The wood-stove heating is an addition to the propane, and obviously won't be in use year round.

Do I actually need a container to be a water heater, or could I use something else that's water tight? Alaska guy used an ammo can. Metal bucket? What's going on inside of a water heater designed to be a water heater that isn't going on in some other kind of metal container?

[Alphaville]

do you have a schematic of the thing?

i looked up the model, saw the photos, and i see mention of a “water jacket” for an additional price, but can’t see the water thing nor how it works

[reepicheep]

This is what I have:

https://cdn.shopify.com/s/files/1/0100/ ... 0.pdf?4483

[Alphaville]

This is what I have:

https://cdn.shopify.com/s/files/1/0100/ ... 0.pdf?4483

ah yeah that makes more sense

off the top of my head that schematic is a bit of a black box in the tank department, by which i mean: that tank needs its own vent and various other things which are not illustrated there.

i’d really consult with a certified plumber here, for several reasons:

1. water spilling out of any part of this setup onto your ceiling (from pipes, tanks, fittings, etc) has the potential to damage your house in a serious way and make your life miserable and costly. needs to be done correct from the outset.

2. steam venting into your house would worsen your existing humidity problem.

3. i don’t know about your area’s regulations or house location, but if there’s any possibility of selling in the future, best to build up to code.

the schematic itself recommends a registered plumber etc but it’s not just them trying to wash their hands off any liability, there are real reasons.

the “trick” here (not a trick) is to find a reliable, knowledgeable, but inexpensive professional through social channels.

i have an electrician like that whom i met through family: the guy is seriously certified, used to work for the state, but now retired, works independently, can wire a whole housing complex, but charges 25% of what a commercial outfit would charge for the same project.

how? where the commercial setup would send 2 laborers plus a supervisor to dig a trench, my electrician and i dug the trench together using my tools. the commercial guys would bring all the parts, my electrician would meet me at home depot.

of course he’s not available all the time, likes to take long vacations, and i had to work aound his schedule, so there are tradeoffs.

i’d strongly recommend a plumber’s supervision for this, even if it’s a simple gravity fed setup and you’re not using a pump or a radiator or any of that.

—

eta: this looks more comprehensive re: hot water tank

http://www.solazone.com.au/solar-hotwat ... ood-stove/

(it’s both wood/solar but shows the tank + outflow tank)

[jacob]

Do I actually need a container to be a water heater, or could I use something else that's water tight? Alaska guy used an ammo can. Metal bucket? What's going on inside of a water heater designed to be a water heater that isn't going on in some other kind of metal container?

Not an expert, but my parents had/have something like this. Theirs was/is an outside system that resided in an adjacent building (they live on a farm). They have had two different versions. A primitive one with just the furnace and a motor driving the circulation into a small tank inside the house, and later a fancy one with expansion tank, an insulated residual tank(*) when they got tired of stoking the furnace all the time (much more awesome). I don't know anything about this aside from operating it.

(*) IIRC it's 1000L+ ... which translates into "a lot of ammo" when measured in freedom units.

The main thing going on inside the water tank is pressure. When water heats up, it expands. Some systems have an expansion tank to avoid overpressure in the plumbing system (that shit ain't pretty, think water spurting out of weak plumbing joints all over the floor or through the walls in the rest of the house system with you desperately trying to cool the stove down). This one appears to have a "safety vent" which might spurt hot water or steam onto your roof.

Otherwise, there's nothing to it but basic physics. The thermal exchanger inside the stove heats the cold water that falls from above in one pipe. Convection (heat rises) sends it up the other pipe. In the tank itself, convection also ensures that the warmer water is on the top in the tank and the colder water is in the bottom. This is why the hot pipe enters at the top and the cold pipe exits at the bottom.

The water heater we have in our basement is the same design. Convection tank with a propane heater driving a heat exchanger and an overflow/safety pipe that's unceremoniously pointed at the sink next to the tank.

As for the ammon can, the main concern is overpressure and whether that pressure has somewhere to go if it gets too high. Otherwise, think exploding/bursting steam engine. IOW, I think it would work, but I don't know how safe or sane it is.

[Cheepnis]

That diagram leaves many questions.

1) How is the "Open Vented Low Pressure Hot Water Tank" actually vented? The only vent shown is marked as optional.

2) If the tank is freely vented to open atmosphere then the supply in must be controlled somehow. Manually? Float switch? Digital sensor & solenoid valve? Otherwise the water pressure will just shoot out your vent.

3) Are there manufacturer recommendations for where in the system to branch off for your fixtures? I would assume somewhere between the heat exchanger and the tank on the outlet side of the exchanger . Which would give all the cooler, though still heated, water in the tank one last trip through the exchanger before use. But I have no experience in this type of system and these things can be counter-intuitive sometimes.

4) Also be aware that you will need to get two BSP (British standard pipe thread) to NPT (national pipe thread) adapters once you're ready for install. Then you will be able to adapt from the NPT to whatever type pipe you're gonna use (copper, pex).

[reepicheep]

Thank you to everyone who responded.

I can't answer all these questions, but I've shown this thread to the person working with me--handyman I've hired for four years on a huge variety of projects, including other electrical and plumbing work--and he's read all your responses and has looked at the literature that came with the stove. He generated a much better drawing than the one I did.

We're still puzzling things out, but I feel good about his puzzling-ability and experience in plumbing generally. I'm also living part-time with a motorcycle mechanic studying to be an electrical engineer, so I'm not all on my own here.

If he has answers to these questions that will help us move forward on the next step, I'll post them.