pjeter schornstein

Hehe, ok, you made me rethink it. I’ll probably just remove the damper or keep it open. But why do you think the amount of heat escaping when the feed tube is closed is negligible? The hot air will continue rising up the chimney even when the feed tube is capped, no?

Regarding the cooling function, I’ll update here in summer. I also want to build a wall-sized swamp cooler to accompany it. Athens is dry and hot in summer, so I think it could all function together.

I watched Paul’s video. It’s cool. I think it’s different from what I’ve done because he’s trying to cool the mass by getting cool air to go into the feed tube, and I want to keep it capped and only let the hot air go out from the ceiling area. If it doesn’t work as expected, I might try his method.

I don’t think I’ll need an extra fan for that because the sun in Athens is intense, but I might add glass on its side to make it a more efficient sun collector.

Thanks for the comment Thomas! I did not think about it...
I think I´ll just use it as I first intended, to keep the heat in after I fire the RMH and I also close the feed tube with firestone

Hey all! So, I finished the RMH and wanted to share the results.

There’s about 4.5m of 8" duct inside the exchange, and after it goes out of the house, it runs 4m horizontally and another 9m straight up. I insulated all the outdoor ducting with 5cm rock wool, tarp, tape, wire and aluminum tape on top. I hope it holds up well.

For the heat exchanger, I used cob and some rocks and plastered it with a mixture of lime and marble dust. I think it looks great and feels great.

I built the manifold with construction metal grid to initialy hold the bell in place. I tried to make it as spacious as possible, so it’s kind of conical. I laid the cob pretty thick on it, so it won´t crack.

The parts that are directly on top of the bell did crack a bit when it’s firing strong. I hope I can just repair it while it’s expanded, but anyway, it’s only small cracks . I would have added fiberglass mesh if I were to do it again. I did tried to make a small gap for expansion but apparently not enough

The RMH works great. I mean, it drafts like crazy and is super easy to fire.

It’s not holding yet heat as much as I hoped, but it is getting better each time, and I think it just needs some time to dry.

I added a few more features:

  - I added a damper at the point where the duct goes out of the heat exchanger. I use it after firing to stop the hot air from drafting out, but I also found it’s good for generally controlling the draft while it’s running.
   -I painted the last two meters of the chimney black and inside the house, I added a port to the duct close to the ceiling. I’m hoping that in summer I can keep this port open and it would function as a solar chimney to draw the hot air out of the house.

Man, I thought it´ll be straightforward but there's some considerations to put in it
I looked again at how I want to set it up and I realized there's some site restrictions and I might have to do it with the insulated pipe running outside anyway because I have a concrete beam running all through above my windows and there's a column running up on the same line with the heater so I think there's only two places I can drill a hole for the chimney ( I marked it on the photo)

I thought I reduce the size of the mass to 140cm from the bell to the end of the bench and insulate the outside chimney, give the 4 meter vertical part a good 70cm slope+ the pipe would be black (It´s a sunny spot  from 15:00 and in Athens its sunny even on most cold days)
Glenn, I looked at some half barrel. it´s like a stratification chamber? It looks really interesting but I really wanted to do a simple design for my first heater..
I would like to have just a low bench.
What do you guys think- would this size of mass be ok to keep the smoke warm enough on the way out? Would going for the 8" system be the right way in this case?

Should I rise the pipe near the bell? If not, how? I thought I can put the last part of the pipe above the first part so that it can heat up a bit. would that help or just have the pipe zigzag instead of do a 180

I´ll add a few sketches of those options let me know if they make seance..

Athens dosn´t get bellow 0 Celsius but actually can get pretty cold inside the buildings because they are not really designed to deal with that.. My place in one space (expat the bathroom so the room is actually more like 70sqm) It´s brick walls and terrazzo floors that turn into a freezer in winter.  my apt in the center of Athens is built in 1965. Its 6 floors of factory spaces and the other two floors are apartments. It used to be a typography factory and some other floors still got those massive pressing machines so I´m less worried about the weight.
My walls are not insulated and the wall exposure is north west and east with very large windows on the west and east  (I´m planning on double glazing them as first part as this winter project). It´s also get extremely hot due to this orientation. The chimney would go on the west side where I have afternoon sun at most days and because of that, I also thought of using the chimney as a solar chimney in summer : make a opening/ cleaning port at the part of the chimney that's inside the house and close to the ceiling to open and draw the warm air out in summer...  Maybe it could be even better without insulation for this reason? If it´ll be isolated I guess I cannot do that.

I can´t run the chimney inside the above properties. The part that would run vertically, I also prefer outside but maybe I´ll compromise if it is very important. Can you tell me why this is an issue? I´ll also mention that above the part of the chimney that would run horizontally, there's a balcony of the floor above so It might add insulation. I am honestly most worried about it not having a good draft.

About regulations.. I lived in Germany before moving here. I am not sure if  it´ll be completely legal. I´m not going to try to get a permit.. I live in a yet very rundown area of Athens and from my window I can see countless building violations.. Also a few of my neighbors has a fireplace. I doubt if its with any permit... I thought best is to locate it above the beam and keep size to minimum.

I´ll add a floor plan of the placement I had in mind. measurements are in cm.

Hey all!

I am planing to build my first rocket mass heater and I thought I upload the plans, questions and eventually the build, knowing there are very experienced people here,
I´m hoping you could help me through it.
I live in Athens, Greece. I´m on the 6th floor of an 8 floor building and it can get cold here. it´s an 85sqm open space. the building is industrial so it can hold the load and     It´ll be placed mostly above a beam.

My first question is if I should do a 6" or 8" system. the 6" (15cm is wildly available here but the 8" seems hard to find and more expansive. All the explanations I find are for the 8" and the space is large. Just making sure, it´s better to insist on the 8"?
2. I cannot put a chimney through the building so it´ll go out through the west side wall, then maybe 4m horizontally (I´ll add upward slope) and then two floors up. this part would have to be insulated, right? would foam/rockwool with some silver tape around it be ok? The insulated pipes I found online are real expansive... anybody has experience with that?
3. I´m pretty scared to install this chimney by myself. I spouse professionals could do that?
4. For the heat riser, I see people use ceramic blanket. Could I use rockwool/ perlite slip or better just order some blanket already?

Does it stop working because the humidity goes up? I bought a temperature + humidity meter to make sure. Its 23:00 now and humidity is at 20 percent with 37 Celsius.
Do you use a commercial one?

Hey,
I live in Athens and it´s getting crazy hot here but dry. I am renovating my new apt. Its 65 open space and I still don´t have ac but the price of electricity here is ridiculously high..
I am thinking about building a swamp cooler. I don´t want to do it just to discover its not that effective so I thought I run the idea in this forum.
I thought of building the wall from clay bricks (the hollow kind with lots of surface area) and some old roof tiles. it would be 130cm wide on 190cm high.
I want to make it like a large box with the reservoir at the bottom and using a pump to move the water and two box fans at the bottom directed upward to blow air to the narrow chamber behind the bricks which would create pressure for the air to go out the front.
I would like to make the whole thing on wheels so I could move it around.

I seen people building it also without a fan, for greenhouses ext. I have crazy wind here coming from my windows in the east and north east. I don't want it directly on the windows so I'm not sure if I can rely just on wind...

Anyway, would it be effective for the place? I like to use less electricity+ its too dry here for me and my plants+ I think it could look so sweet and I like the sound of water..

The apt is 80sqm. Its one large room except for the bathroom. it’s uninsulated masonry . The biggest wall with large windows (single glazed) directing west. I want to put the RMH perpendicular to the wall directing north (no windows) in the middle of the room with the heat raiser directed to the room and either put the exhaust chimney from this wall ( if its a short chimney because there’s no windows in this wall and no way to secure it all the way to the roof) or going out to the small wall directing south and to the roof.
I think a small system would be great. It’s not really getting cold for long stretches and gets warm a lot (attached the temps) but I’m not sure how it is in that smace.
What manual should I use to make a smallest system? Is it the one with the smaller pipe diameter?
What’s your opinion about the exhaust pipe?