Rocket Mass Heater first few test fires

Hi

If I could figure out how to add photos I'd post those too .............

<iframe width="560" height="315" src=" http://www.youtube.com/embed/2Uefwq4cXHY"; frameborder="0"
allowfullscreen></iframe>

<iframe width="560" height="315" src=" http://www.youtube.com/embed/ci4I1XISNKo"; frameborder="0" allowfullscreen></iframe>

<iframe width="560" height="315" src="http://www.youtube.com/embed/XEUnWu3QsqM"; frameborder="0" allowfullscreen></iframe>

Looks good. I like that way of adding mass to the system... quick and easy.

Yep, but still not the right spot for the mass. 

Well give me a day or 2 and I'll add more mass 

but since you mention it why not ?? more mass = good mass ?

Roger

ps anyone figured out how to add pics 

Satamax wrote:
Yep, but still not the right spot for the mass. 

In this case it is... This is a green house and requires a slow steady heat. Leaving the barrel with no mass around it in this case would steal precious space from plants because it was too hot for a long way from the exposed barrel. There is room for a low bench to set plants on and it sounds like he is going to do that too. The purpose for the exposed barrel in much of the literature I have read is to give "quick" heat. Some of the comments I have heard have been.... too much quick heat... have to stop burning before the bench is warm to keep the room from being too hot. The design is not new... in fact it has been around in the masonry heater world for over 100 years... made of brick. It works. both steel and brick (or even cob) conduct heat well, better than air. The magic in the RMH seems to happen mostly in the riser where the warming/expanding air gets lighter and rises on it's own. The cold steel (at first anyway) does chill the air as soon as it hits the top making it shrink and become denser/heavier and fall. Having mass at that point will actually keep the top of the barrel cooler longer than air would... and may work better. This one was certainly not having problems and mine (whatever problems I had in the burn tunnel) has never had smoke back problems either.... So much for the "The barrel must be exposed" myth. Not so. I think it does need to be kept cool (relative term here, secondary burn may be 1800F or whatever, but the barrel seems to max out around 400 to 600F Mass or no). Using an insulating brick could be a bad thing... but not a problem as those ones cost a whole lot more than normal heat conducting fire brick... 4 times as much anywhere I can find. Regular clay brick (which is fine for anything out of the flue path is even cheaper (more often free) and still conducts heat well. A second layer (if needed) could even be concrete bricks.

In the end, whatever works, works. No matter the theory written in the book.

Sorry for being so serious about a comment obviously written in jest... I did take it that way first and chuckle. However, I am pretty sure that for this use, the mass is in the right place. Just as your shop unit may be best with no mass because of the large space needing heat. You have the brick though, so try it both ways. A lot can be seen even from dry stack methods.

RNM35 wrote:
Well give me a day or 2 and I'll add more mass 

but since you mention it why not ?? more mass = good mass ?

Roger

ps anyone figured out how to add pics 

To post pic you can click on 'quote' or 'reply' then click on 'Additional Options..."  Then "Browse"  and attach pic.

Hey Len, it was just  a kind of joke.  It's just my opinion, and i'm no expert.

Mass around the barell might cool it down faster in the starting and warming up  sequence, but i'm always under the impression that the temp differential gonna be impacted by covering the radiator, after a while. I know that air is a good insulator, but it moves around and takes heat away. Definately water and radiators would be better.  Thoses bricks, dunno! And earth, dunno either.

Satamax wrote:
Hey Len, it was just  a kind of joke.  It's just my opinion, and i'm no expert.

Mass around the barell might cool it down faster in the starting and warming up  sequence, but i'm always under the impression that the temp differential gonna be impacted by covering the radiator, after a while. I know that air is a good insulator, but it moves around and takes heat away. Definately water and radiators would be better.  Thoses bricks, dunno! And earth, dunno either.

My last test was about 6 hours worth with 3.75 inches of brick around the barrel. No smoke back... but no long run through a mass either. Testing looks good so far. I have seen another used water heater sitting in my travels... i will ask today if I can have it   also some used 6 inch ducts at a different place.

Ok photos of the build process - I'm not a metal worker . ..... which I guess is obvious 

Can't weld. Limited tools to hand and no money - So this is built with stuff from the scrapyard and a jigsaw - that's it

Work in progress I'll keep adding stuff

PLEASE tell me what I get wrong 

PS can you tell I'm single making this in the kitchen lol

Ok couple more photos

Couldn't find any pipe for the outer of the riser so made one in some sheet steel I had at the allotment - yeah I know its an odd shape but it just sort of happened 

I didn't take a pic of it but I cobbed over the top of the insulation

Internal riser diameter 5" (its what I could get) and rock wool insulation on the basis I had some.
I rejigged the outlet a bit to increase the area - packet out the base with some really awful soil (full of broken glass - its an allotment hazard) 

From adding the barrel its on video 

Ok thought I'd just update this - its nearly finished

Its ended up a 5" system with 25 feet of 5" ducting that reduces to 4" as it exits the greenhouse. Works really well The exhaust is barely warm.

I've got to add some more cob to the barrel and clean up some of the mess but spend way too long fiddling with the fire and making coffee !!

Roger

I believe it's standard practice to burn any paint and coating off the barrels before use. there are very good reasons for this. if you can't easily break it down to do this, consider pasting newspaper on with clay as a sort of papier-mâché. might help contain some of the toxic stuff you're likely to produce when that barrel gets hot enough.

Hi

The painted barrel is an outer case - containing mass surrounding the actual burn barrel - so it doesn't get hot enough to be a problem It just acts as a radiator and protects clumsy me burning myself on the inner barrel as I walk past !!

Roger

I like it. I have been considering different designs for my RMH here in my place because it is 1. a mobile home and 2. space is limited for mass. I like the idea of surrounding the heat riser with a barrel filled with mass from a safety factor. I found the biggest problem for me would be clearances from combustible materials and a barrel filled with mass solves that very nicely. Thanks for sharing. Peace.

Roger Merry wrote:Hi

The painted barrel is an outer case - containing mass surrounding the actual burn barrel - so it doesn't get hot enough to be a problem It just acts as a radiator and protects clumsy me burning myself on the inner barrel as I walk past !!

Roger

right. I suppose if I had watched your videos, I would have noticed that. looks good. carry on.