[Stoves] Heat / cook stove - proposed design

[John Davies]

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: stoves-bounces at lists.bioenergylists.org
[mailto:stoves-bounces at lists.bioenergylists.org] 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