Michael Solosky

Look up a German company called "Lehm und Feuer" (Clay and Fire). They have been creating works of art wrapped around fireplaces for years. Their gallery of past projects is inspirational to say the least! Best of luck

A big shout out to both Glen and Satamax for your input. Awesome brothers!

Update: Yesterday I burned the reconfigured RMH. The changes I made were to increase the size of the exit to the manifold to approximately the same size as the feed tube, lifted the barrel to approximately 2-1/4" above the heat riser discharge and slightly increased the slope in the ducting. Results...It rocketed!!! Not exactly an Atlas 5 to the moon rocket but more like a large fourth of july bottle rocket but it DID rocket! I was able to burn it for a good 4 hours and other than the initial warm up of the system it didn't back draft. Now mind you it was quite a calm day and I did start it up with a small duct fan at first but when it was up to temp the furnace didn't kick on at all. Amazing!

To further increase the rocketiness ( is that a word??) I'm going to replace the Heat riser with a 6 " one that is the height of a full size barrel, recalculate the height of the barrel above the heat riser discharge and reduce the length of the ducting in the bench. I also plan to build and improve the exterior chimney. Of course this will have to wait until springtime as I plan to build a conventional chimney that will extend above the roofline to and the ground here is definitely frozen.

Questions: Has anyone experienced the top of the barrel concaving down towards the heat riser? I think I need a new barrel...

Also, Where can I find plans for an exterior chimney that will work well with a rocket stove?

Good Morning! I've increased the size of the manifold discharge by removing the original piece of ductwork and chipping out / grinding to make it bigger. I think it's now larger than the feed tube. Thank you Antone and Staci! Also, I raised the barrel to make a 2-1/4" height above the chimney riser. I think it was too low before and choking out the fire. Brad, if you look at the cleanout above and behind the barrel you can see a cap with a handle.  I'm thinking of installing a draft fan in the tee that will blow directly out the chimney. Cold air in the ductwork would be entrained in the flow creating an artificial draw but wouldn't be directly in line with flow path. After the system is warmed up it would be turned off and capped. Gonna think this one through some more after I see how yesterdays mods work out. Staci, thanks for your well laid out thoughts and ideas. I'm working my way down your list. I can't tell you how good it is to have you and all the permies as a resource to help me think all this through. I re-mortared the barrel on last night and won't get a chance to burn it until tomorrow morning. Fingers crossed!

Brad Weber, thanks for the idea! It may be just the thing to get it flowing in the right direction after I make a few modifications. I have a 6" duct fan that I think I'll Mcguyver into the system and give it a try. Cheers!

Satamax Antone, I'm sure your right! I'm going to knock out the exhaust manifold and expand it which can't fail to increase the draw. Next big question....The distance from the seal of the barrel to the bottom of the exhaust manifold is 17 inches. In other words, the exhaust is forced down 17 inches before it can naturally rise up the sloped duct work. Is that too far?

Hello and Thanks to all who have given me some thoughts on the problem. Your kindness is much appreciated! First to answer a few of your questions...

Yes it's in the basement, this is the only space that I have for a fireplace in my home. The exhaust exits through a 6" hole cut through a foundation block. It then goes into a short insulated piece of pipe (30") and out a short chimney ( 36") with a rotating cowl on it to reduce the down draft.

The brick column at left of my RMH was a chimney installed in 1900 when my venerable old house was built. Most of it was removed prior to me. It only goes up to the top of the basement and dead ends. I placed the RMH next to it so that it could act as additional thermal mass. Also, this location is in the center of the room.

I've tried burning with a window open. Doesn't help much.

The chimney inside the barrel has a diameter of 8 inches. The ducts are all 6 inch. (Possible problem?)

Also, the size of the manifold opening, made from a duct boot, may be too small to accomodate the 8" internal chimney. I tried to fix this by chipping it back to increase it's size convinced that this was the culprit. Nada! Nyet! Nothing!

It's an L tube right now because the J tube I constructed didn't work. It only seems to draft if I push the fire directly under the chimney and constantly babysit it. Then only a little bit. If I can get it to draft properly or, dare I dream, actually Rocket, I'll reinstall the J tube so that I can auto feed the fire.

There is no mass portion to the bench because the system works so poorly. Seems ridiculous to fill it up until the system is working properly since I may need to modify the ducts. I've covered the pipes with fiberglass insulation to keep them warm while testing and it does help, but not a lot. Also, I don't have access to clay with which to make standard cob. I live in a city and there isn't any clay in the yard, or for sale at the local dirt suppliers, Home Depot, Lowes, etc. I've checked in a 60 mile radius from home with local excavators, masonry supply stores, etc. but it's just not available. So I'm going to be using a product from the local dirt sifter place that clumps together well when mixed with a little portland cement and water. I have a few yards of it standing by for when the drafting problem fixed.

I removed the portion of the duct that extends into the second bench section shortly after the picture was taken last fall. That DID help the draft somewhat but definitely didn't solve the problem.

Another thing I've noticed is that the distance from the bottom of the barrel to the bottom of the manifold is 17 inches. In other words, the exhaust has to be forced down 17 inches before it can naturally rise through the ducts. Am I making the system try too hard?

I'll take some pictures now and get all the dimensions and be back soon. Thanks Again for talking me off the cliff....

Thanks for your kind words, and thoughts. i'll be posting more pics in a few minutes. In the mean time I'll start my own thread.

HELP HELP HELP!!! Why doesn't my rocket mass heater draw?? Is there anyone out there that can help me figure out what I've done wrong in constructing my RMH? I have many pics of the build and really need a discusson on the phone to see if I can straighten this thing out before I consider my 800 dollar inverstment a total loss and take a sledge hammer to it and forget the whole thing. I absolutely cant burn it without massive backdrafts and filling the house with smoke. To be frank, at this point it's a fire hazard. PLEASE SOMEONE REPLY! It's February here in Michigan and I need to my RMH to partially heat my house.