6" RMH Build

[hpmer]

My experience is it definitely would. I've built several different sizes from 4" to 8" and the larger you go the bigger the output. I was quite surprised the first time I went from a 4" to a 5" how much of an improvement there was.

Granted mine are all cook stoves, but a core is a core, I just feed the exhaust to the sky rather than through a bench so the same general rules should apply.

If there was any way to increase the size, even a little, I bet it would be WELL worth the effort.

[DevilsBrew]

[mannytheseacow]

[pa_friendly_guy]

Life style changes can be hard Manny. Do you plan on not being a Hermit and bring in company to keep warm? Or do you plan on drinking more homebrew? Or do you just plan on putting on a sweater and long pants ?

[mannytheseacow]

Hahahahahahahahhaha! I'm hoping a nice wool sweater will suffice!

[matt walker]

I vote for more homebrew!

To those that asked, yes, 8" has much higher output than 6". The fact that Manny's barrel runs at the same temp as mine is a testament to his superior fuel, and it does show, like you say Manny, that your system is running very well.

You've got a HUGE mass, in my opinion. I would be surprised if it's dry, very surprised. The evaporative cooling going on in there is surely robbing you of heat, and I believe your bench is going to continue to warm over the coming months. Also, you haven't gotten the warmth to the stack yet. Higher stack temps, and cooler outdoor temps, will speed the flow of gasses through the system and you will start to have higher temperature exhaust running through the bench. I think it's going to get warmer, but it's going to take a while and maybe a long weekend of just cranking the thing to see if you can get the exhaust up. I feel that once you do get warm at the end of the system it's got such a huge flywheel it's going to have a lot of momentum and should not only stay there, but you'll start with the bench over 100°F so the exhaust will start there too, and only rise from there.

My neighbor came over for a visit on my bench yesterday evening and we talked about your system. He runs a six inch system in a little homemade tiny house. He's a badass, btw. Anyway, he has a much smaller mass, and a 30 gallon barrel. His barrel runs typically 400°F, and he says his bench is cooler than mine, typically around 120°F. He did something interesting, which he is very fond of, and I think it's a pretty cool concept. He ran 4" dryer ducting between the nearest wall and his barrel and then cobbed up to enclose the ducting, contacting the rear 1/3rd or so of the barrel. He uses a small 12v computer fan to move air through there. He gets 134°F air from that ductwork which he directs towards his kitchen. He says he can really even out the heat in the house that way. That was a tangent, but I remembered I wanted to share that while we were talking about systems. Anyway, his assumption is what I posted above Manny. Still some moisture in there, really large mass for a 6" system, and still cool exhaust temps meaning slow flow meaning lower internal temps.

I'm with you on the idea that it's working correctly. Every system is balanced differently, and yours is going to show it's character here. One thing about that huge mass, I have a feeling that you won't get much cooler inside even as the weather cools. That mass is just a huge flywheel, and while it's not going very fast, it would take a huge ton of energy to slow it down, as it were. I think you will only get warmer as the winter progresses.

[mannytheseacow]

The idea that there is still water in my bench has been on my mind, also. I've never seen the steam on the windows as you have described in other posts. Not to mention, at the temps I'm seeing it's not going to be steaming too much water out of the bench. I often have a dehumidifier running in my basement and for a while I was pulling several gallons a day out of it but then I hit a plateau where the dehumidifier wasn't really capturing anything anymore. A couple of weeks after I posted the picture of my bench with the cushions on it I was pulling them back to plaster the armrest and found mycelium growing through the wool blanket under the cushions- good indicator of a lot of moisture. Since then I have removed the cushions and just have the wool blanket there (2layers) to keep the heat in but allow moisture to wick away.

Couple of other comments while I'm here- The last several nights I've spent the evening working on the computer, sitting on the bench which daily turns into laying on it and finding it very hard to relocate myself to bed. These things are quite luxurious. I'm seriously scheming a heated bed in my future.

Also just want to say one more time how valuable this community is. My career in science has really taught me a great appreciation for peer review, and it's really great to get it in the context of this website for all these home concepts. Thanks for all the input, everyone!

[DrewInToledo]

Manny,

May I ask what the distance is between the nearest edge of the barrel and your wall? It seems that you didn't use cement board like rjdudley.

It would be nice to hear from rjdudley to compare distances as well. How about you, Matt? I know you have a brick wall, but wondering if it collects radiant heat.

I'm just gathering data and doing some planning...

Drew

[mannytheseacow]

Hey Drew,
I'm at >24". Out of town on business or I'd get the tape measure out and give you a better answer. There's a good distance back there. Between the barrel and the wall is 6" of space, 6" of exhaust, 6" of more space, then the width of a cinder block chimney faced in limestone. I'm not sure if you can see it in the pictures but there's a little reading nook back there with a little shelf to set your, ahem, "beverage" on.

[matt walker]

Mine's actually <6" at it's closest. Made me nervous for a while until my lovely neighbor pointed out how my old wood stove sat there going mach 99 for 30 years and made me feel better. It for sure is additional useable mass, and the wall is how I started thinking along these lines in the first place. The barrel is HOT, so clearances are fairly important, I would say.