Hi, just trying to make sure I understand how this works before getting my hands dirty!
I've read the book. Listened to the loooong podcast. Looked at tons of videos. Studied Erica and Ernie's photos. Read many threads here. Now I need to know if I've got a grasp of the basics. So:
The RMH has the chimney (AKA riser) next to the feed tube so the flames go up the riser and heat it. The riser MUST be insulated to hold the heat in. Then the hot gases rise to the top of the riser and go down the outside of it, but inside the barrel. The gases MUST cool fairly rapidly in order to keep the draft going and prevent back draft. The top of the barrel gets very hot and this is a good spot for a large pot of water. The sides of the barrel near the top are very hot and it cools off as you go down the outside. This warms your space right away which is needed since most of us won't think to build a fire until we are uncomfortably cool. The remaining heat, what would be wasted in a conventional wood stove, moves from inside the barrel into the ductwork under the bed mass. Once the bed mass is warm it stays warm for many hours and you can sit or lay on it for a comfortable warmth.
It is critical to have your cross sectional area in the ducts and the entire run of the gasses to be the same as the cross sectional area of the riser. This is what gives the rocket effect and burns all the volatiles from the wood. You cannot have too large a cross section on your air intake without getting burn back (flames traveling back up the fuel). The J tube feed allows the fuel to continually move into the hot area and burn without needing constant adjustment. You need the bottom of the barrel removed and you need a barrel with a lid that fits tightly, but can be removed so you can occasionally clean out fly ash. The fly ash will compromise your cross sectional area and reduce the rocket effect and you will then have smoke coming out the exhaust.
(Can't build it till I move, but learning all I can and will order plans so I don't have to do all that figuring. Don't want to have to pull it all out and start over either.)
Kim Kingbold : That was a very clear and simple spoke synopsis of the way your Rocket Stove Mass Heater works . If I were trying to explain it to some one who had never seen one i would compare it to one of those Propane or Natural Gas Monitor Heaters that are installed at an outside wall, burn very efficiently before passing through a heat exchanger, before going through an outside wall, they are certified to allow the use of a plastic pipe for exhaust discharge ! Our Rocket S.M.Heater goes thru a heat exchanger with a great thermal mass before it exits the building at around 100 -150 degrees F . - Pyro-maticly yours Allen L.
Check-in with the good folks at www.cobcottage.com, and at www.ernieanderica.info and search for Rocket stove and Cob workshops in your traveling area. If you think you deserve a break in the price of a work shop be sure to ask the local Host if you can help on set-up work and take the training at reduced cost, just make sure you both have a clear understanding of your duties, and when they end A.L.
Success has a Thousand Fathers , Failure is an Orphan
LOOK AT THE " SIMILAR THREADS " BELOW !
posted 6 years ago
Thank you, Allen, I'll look into a workshop once I'm moved. In the meantime will keep studying.
Location: Northern New York Zone4-5 the OUTER 'RONDACs percip 36''