Tuve Lundberg

Peter van den Berg wrote:

It might be a good idea to study the batchrocket website. Most information is there, including drawings and examples. The link is to the English version, the site is in nine languages although to date nothing in Swedish.
Lots of information to digest, also how bells work.

Oh, yes, now I see it's your site. Found it yesterday. But it'll take me a while to read it all! Taking it in portions.

Thanks, Peter!
Lots of new things for me to learn about, since most of the things you mention here is new to me! I will visit that site.

I'm sending out some emails to find out the inner diameter of my chimeny, and how much weight my floor can hold. 2500 kg on how much floor surface? If it is not a bench, I guess it's heavier per m² instead.

I did get some specifications from the company that built my barrack home. Not in the form of "you may load X kg/m² on it". More "this is the type of board and this is the dimentions of the beams, go and ask someone else what that adds up to". Not sure who that "someone else" is.

Forgot to mention: I do intend to add a slanted roof, which will change how high above the ridge the chimeny reaches, but I also calculated that when I do, I might need to add a section to make the chimeny higher too.

Peter van den Berg wrote:
This is greatly depending on your climate, the orientation and insulation of your house.

I don't know how many kWh I need. My house is 840 x 590 cm big, with one of the long sides towards south, with biggish windows, giving me some amount of passive solar, if we get sun in the winter, so far, this winter almost none.
The house is actually two builder's barracs connected to each other. The outer walls have 95 mm rockwool insulation, the roof 120 mm and floor 145 mm.
Southern Sweden har variable winters, both in temperatures and duration. Imagine just a little colder than the Netherlands, and almost as moist.

Peter van den Berg wrote:
Since the house is small, a single bell might be better than a bell/bench combination.

My main aim is to store heat. My current stove doesn't do that.
My (limited) understanding was that a heated seat gives so much more efficient heating than radiating the heat into the room. Will a single bell  keep the house warm 24 hours on only one firing?

Peter van den Berg wrote:
My heater is about 10 cm away from a wood stick/ plasterboard wall. On the wall behind the heater is a steel corrugated plate mounted on spacers. While the heater warms up the plate, an air current will start which in turn cools the plate. When my heater is too hot to touch this heat shield is still about hand warm. Works wonders!

Coll, I have something similar for my current stove, I might even be sble to reuse those.

Please don't build a piped bench, if at all, coupled to a batchrocket system. This specific combustion system is very picky about friction in the smoke path..

That's a disappointment...
No thermal mass, no heat storage? Or does it do that another way?

Peter van den Berg wrote:
As long as you run the heater every day you'll find there won't be a problem. Lighting a warm heater is the easiest, by far. You might get problems while drying out the heater and further down the timeline, starting up a stone cold heater in autumn. A bypass would be a very handy in this regard.

I don't know enough about bypasses.

Peter van den Berg wrote:
Question from my side: what's the diameter and height of your existing chimney? Is it straight, cylindrical, smooth inside and higher than the top ridge of the roof? No other buildings or trees nearby?

I attach a photo of the chimeny above the roof. No trees or obstructions. About 130 or so cm above the roof, 165 cm below the ceiling, and I guess about 20 cm through. I can't see the inner diameter. It is insulated  and about 22 cm outer diameter. I have a lid cover from the stove which is 174 mm in diameter, wich might correspond to the inner chimeny diameter. Straight up. Probably smooth.
But depending on the rmh design I choose, maybe I need to put a bend on it, to avoid it coming down straight on the heat riser.

I'll try to show the inside space in a later post.

Hi!
I just started trying to navigate in the wonderful world of rocket mass heaters. I want one! (Or several, in the greenhouse, the workshop, etc.)

First batch of questions:

How do I choose a suitable dimention for the needs of my house? It is only 44 m².

My house is small, and the space for the burner part is limited, how compact can they be, and how close to a plywood wall?

I was thinking the thermal mass could replace my current sofa, but due to the geometry of the room and placement of the current chimeny, maybe I should make a corner sofa out of the mass. But then the pipe length would be something like 11 metres. I have no idea if that is too long.

I live in a climate with wet, foggy and windy winters, temperatures most of the time slightly below or above freezing. I think I need some way to help the draught start in the right direction.

And how do I stop the draught pulling the warm air out of my house between the fires?

I read about batch boxes today, and I can see how one anxious teenager in the house is really going to be relieved at having a closeable door. The open hole would freak them out.

Please, be my guides on these first steps of my journey! Assume that I don't know the american names of materials and components, as I'm Swedish. I may need just a bit more detailed explanations of special words. Please bear with my metric brain...

Great! Thanks!

Jeremy VanGelder wrote:Tuve, Peter Van Den Berg's website has both metric and english measurements. He is based in the Netherlands.

BatchRocket.eu

thomas rubino wrote:Hi Tuve;
check these out) https://permies.com/t/155372/Installing-Bypass-bell
https://permies.com/t/159700/Retrofitting-Piped-Mass-Bypass-Install

One thing about RMHs is, once you get your mass up to operating temperatures you will not have draft issues.
All winter your RMH should start with no problems.
Starting a cold RMH can be a minor problem.
By installing and using a bypass that issue is eliminated.

Thanks!
I must admit, though, that I am struggling at this forum, for several reasons. My English is good enough, but many of the technical terms, names of materials, components and tools etc are unknown to me. And then I need to painstakingly translate all sizes and temperatures to metric and Celsius. On top of that I have never yet seen a rocket mass heater irl, and I'm trying to follow the discussion between people who have already built several.

I am only at the beginning stages of figuring out how to design a rmh that will suit my house and climate. Maybe I should start a "metric newbies" thread?

The mass and ability to store and slowly release heat is my main reason for wanting a RMH, so for me, the bypass options would be what I need to learn about.

Do any of you know where I can find more info?

Hi!
I'm very interested in building a RMH in my semi-tiny house in southern Sweden.

One thing I'm pondering is how to get the smoke going in the right direction as you first light it up?

I've been looking at youtube, and so far not seen one being lit. However in one video it was mentioned that draught automatically goes the right way when the temperature difference between outside and inside is big. Thus long, extended spring or fall is not ideal. Also it is mentioned that wind can blow the smoke in.

In my part of southern Sweden, the entire winter can be foggy, rainy, windy and a temperature that fluctuates just a little above or below freezing. My conventional, modern cast-iron fireplace is hard to start a good draught in in foggy or rainy weather. So how would it be with a much longer pipe with bends?

Do any of you have a RMH in such a climate? How easy is it to light without smoke coming in?

I tried attaching a video (mp4) using the upload-function. But I guess it's too large. Where can I see what the upper size limit is?