<html><head></head><body data-blackberry-caret-color="#00a8df" style="background-color: rgb(255, 255, 255); line-height: initial;"><div><blockquote type="cite" style="font-family: sans-serif;"><div dir="ltr">Greetings all</div><div><br></div><div>>>(I have noticed that an air leak below a secondary air hole can cause incomplete combustion at that hole.) It is best to supply stoichiometric oxygen so that reactive and less reactive gases burn together.</div></blockquote></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><span style="line-height: initial; font-family: sans-serif; white-space: pre;">> </span><b style="line-height: initial; font-family: sans-serif;">[RWL Agree with most. But I think one will get a considerable amount of unburnt gases if one tries for a stoichiometric mix. Even a gigawatt scale coal plant doesn’t try for that. Crispin has argued for 50% excess air I believe.</b></div> <div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">Power plants tend to be able to control 'everything' and have about 7% O2 which is 50% EA. It is a rare stove that works well below 70%. </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><span style="font-size: initial; text-align: initial; line-height: initial;"><br name="BB10" caretmarkerset="INVALID" class="markedForCaretMarkerRemoval"></span></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">However just to share a surprise the BLDD6 from SeTAR optimises at 30% EA which I found strange. It has tangential secondary air running into the base of a cone which draws into a smaller diameter flame tube (1/2 the diameter of the cone = 1/4 of the area). The vortex stirring is vigorous. </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">It is literally the only burner I have seen that runs best in such a low EA condition. </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">My general advice is to shoot for 50-100% EA for highly predictable fuels and 70-120% for 'wood' then tune to suit. </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);"><br></div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">Regards </div><div style="width: 100%; font-size: initial; font-family: Calibri, 'Slate Pro', sans-serif; color: rgb(31, 73, 125); text-align: initial; background-color: rgb(255, 255, 255);">Crispin </div></body></html>