HI Darren, I suggest that you do not fit a valve at the bottom of the chimney. This could cause the stove to swing to positive pressure, with combustion gasses leaking out of the stove. Rather make sure that air cannot leak into the stove, and that your air intakes have sufficient throttling.
One way to reduce chimney suction is to make a few holes at the bottom of the chimney, with removable plugs. A little cold air bleeding into the chimney makes quite a difference. I have done this with my coal stove which has no throttling on the primary air. It reduces the heat output, for days when it is not so cold. And keeps the primary and secondary air in the correct ratio. Happy experimenting, John Davies -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Darren Sent: 23 March 2012 07:34 PM To: Discussion of biomass cooking stoves Subject: Re: [Stoves] Heat / cook stove - proposed design Finally got a chance to write up my further experiences... I replaced the broken glass in the door into the combustion chamber ..................... I currently have a butterfly valve in the primary air inlet - can block the secondary air inlets (although this appears to have limited effect on combustion) I intend to fit some kind of valves to these. I also intend to add a butterfly valve in the bottom of the chimney. Best Darren _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://www.bioenergylists.org/
