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Thank you everyone for all responses - most helpful.<br>
<br>
I should have made clear that really I need to be able to burn sawn
logs and branches as sometimes this is my only fuel option.<br>
<br>
In response to AJHs reply -<br>
<br>
<br>
On 01/01/2011 22:57, <a class="moz-txt-link-abbreviated" href="mailto:ajheggie@gmail.com">ajheggie@gmail.com</a>. wrote:<br>
<blockquote cite="mid:201101012257.41739.ajheggie@gmail.com"
type="cite">
<pre wrap="">
</pre>
<blockquote type="cite">
<pre wrap="">catch a fair bit of the excess heat in the heat storage.
</pre>
</blockquote>
<pre wrap="">
What sort of heat storage? </pre>
</blockquote>
<br>
I'm going to use a tank of water for heat storage and have a heat
exchanger which I can place on/off the stove. This needs to be
relatively low so that I can use a thermosyphon effect to transfer
the heat up into the tank.<br>
<br>
<blockquote cite="mid:201101012257.41739.ajheggie@gmail.com"
type="cite">
<pre wrap="">Any heating of this should be well separated by
insulation from the combustion area which should be kept hot.
</pre>
</blockquote>
I'll bare that in mind<br>
<blockquote cite="mid:201101012257.41739.ajheggie@gmail.com"
type="cite">
<pre wrap="">too much cross cutting. The little Jotul 602 I have had for 30+ years has
almost exactly these dimensions...
</pre>
</blockquote>
I'm familiar with the Jotul design although must confess not its
entire working principle.<br>
<br>
I found this page which has a diagram which basically matches the
design I'm now making in my head - sloping grate to help the
fire/embers build up in front of the mouth to the combustion
chamber.<br>
<br>
The Resolute Acclaim.<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.hearth.com/econtent/index.php/wiki/Downdraft_Stove_Operation/">http://www.hearth.com/econtent/index.php/wiki/Downdraft_Stove_Operation/</a><br>
<br>
I was thinking of having the primary air coming in low down on the
front of the stove and the combustion chamber insulated via a two
skinned wall, with air gap. I guess this air gap could be used to
pre heat the secondary air which would be drawn down from a valve
outside at the top of the stove.<br>
<br>
<pre wrap="">"There is a big problem with loading large amounts of fuel, downdraught and
tlud get around most of these but the type of layout you suggests will
almost certainly tend to thermal runaway with large loads and dry wood. "
<tt><b>Is it not possible to keep the rate of burn in check by regulating the amount of primary air?</b></tt> <b>Or is this not desirable?
</b></pre>
The other thing thats been bugging me is that for about 20 years now
I have seen clean burn stoves offered for sale. I've never seen one
or seen how they work but the picture show a glass door with flames
going up....<br>
<br>
I think this shows the function<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.woodheat.org/technology/noncatalytic.gif">http://www.woodheat.org/technology/noncatalytic.gif</a><br>
<br>
I dont quite understand by what mechanism some of the gases are
drawn back down from the front top, inside the front door, back down
through the fire. I guess this is however not an idea design for
good combustion.<br>
<br>
Thanks again everyone<br>
<br>
Darren<br>
<br>
P.S.<br>
I just found this page about the SEDORE which has a nice cut away
diagram<br>
<a class="moz-txt-link-freetext" href="http://www.sedorestoves.com/easterncanadaabout.html">http://www.sedorestoves.com/easterncanadaabout.html</a><br>
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