[Cob] (Cob) Rocket Stove, Down Draft

[Shannon C. Dealy]

On Sat, 17 Jan 2004, michael wrote:

> Shannon,
>
> I was wondering if you have taken one of the Cob cottage pyromania workshops?

Yes

> Is there any difference between and rocket stove and a down draft stove?

Depends on your perspective, Cob Cottage uses the terms interchangably
for their stoves, but your link refers to the Aprovecho rocket stove whose
design is a little different.  The Cob Cottage stove designs while they
can be used for cooking are usually designed primarily for heating
efficiency, while the Aprovecho designs are targeted more at cooking
efficiency.

[snip]
> But i like the idea and space saving factor of a down draft, rocket or jet
> stove.  When i saw one at the Cob Cottage heart house site they had it
> running through they're greenhouse - the pipe or flue that is.  At the end
> there was hardly any smoke coming out. Isn't this one of the benefits of a
> rocket stove?
[snip]

The advantage of the Cob Cottage bench stoves over most wood heating
systems is that not only do they get virtually 100% combustion efficiency,
but they manage to unload most of the heat from the exhaust into thermal
mass in the building before venting to the outside (one such stove I
worked on had an exhaust temperature of 105 deg. F., all the rest of the
heat stayed in the building).  The only stoves I know of that do anything
comparable are various masonry stove designs with folded flues, typically
associated with Russia, Sweden, etc..  The advantage of the Cob Cottage
design is that it can be built for little or nothing and requires very
little skill, where the other designs typically cost a great deal of money
and require a great deal more skill (I have heard that paying to have a
Russian or Swedish Masonry stove built by someone will run $10,000 and
up).

Shannon C. Dealy      |               DeaTech Research Inc.
dealy at deatech.com     |          - Custom Software Development -
                      |    Embedded Systems, Real-time, Device Drivers
Phone: (800) 467-5820 | Networking, Scientific & Engineering Applications
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