Dear Tami I am definitely in need of a set (prescribed) rule here. I do have the capability to weight the entire stove to 2 grams and we do watch the fuel burn and the water temp rise. This is very good for the short time (3 or 4 mintes) until the water starts boiling and then it is a guess thereafter because some of the loss is water and some is fuel. As I want to measure the CO and CO2 from a cold stove being lighted (which is when the combustion is worst) I will have to have something that stabilizes in a lot less than 11 minutes becase that is three times as long as a typical test! While I am interested in what the steady-state burning efficiency is, the interesting parts are: - lighting up, - putting a cold pot onto a hot fire, - adding cold fuel to a hot fire and - changing the amount of incoming air volume dramatically, either up or down. It is possible to use waste heat from the fire to preheat and dry out more fuelwood and if it is worth it, we can do that systematically. Regards Crispin - Stoves List Archives and Website: http://www.crest.org/discussion/stoves/200209/ http://crest.org/discussiongroups/resources/stoves/ > Stoves List Moderators: Ron Larson, ronallarson@qwest.net Elsen L. Karstad, elk@wananchi.com www.chardust.com Other Biomass Stoves Events and Information: http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy http://www.crest.org/articles/static/1/1011975339_7.html Gasification http://www.crest.org/articles/static/1/1011975672_7.html Carbon List-Post: <mailto:stoves@crest.org> List-Help: <mailto:stoves-help@crest.org> List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org> List-Subscribe: <mailto:stoves-subscribe@crest.org> > For information about CHAMBERS STOVES >http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm