Need some advice re the burner

[Rthrelk]

Hello everyone -
 
I'm a newbie here and am making my first heater using the Roger Sanders plan, which I've tried to follow as closely as possible. I have the unit in a test state, meaning I've constructed it, welded holes and gaps, installed a door and had an aluminum burner made. wont stay lit after priming. For purposes of testing, I've been dripping oil into the airpipe via the copper line using an IV apparatus, but let the burner get good and hot first.  After letting the kerosene do its initial burn, I add just a little more to get the burner hotter, then start a slow drip as indicated in the plans. However, even though the burner gets hotter than heck, once the kerosene burns off, I get a flame out and not sure why. So I have several questions: 1) are these units dependent on precision conformity to the plans? For example, roger says the flue pipe should be a min of 6". Well, mine is, although it is double walled, making the inside diameter more like 5.75 2) it there a sensitivity to the distance between burner and end of the air tube. 3) what about the air restrictor? He says 80% restriction. 4) would outside wind, even though fairly light, impact anything? 5) any ideal height of the burner from the air tube? I've attached a pic, which shows it in rudimentary state for testing. Thanks in advance for your advice !

[Russ]

Looks like you have a nice start there, although the flame out is definitely a problem.  Unfortunately I cant offer you much help as I dont have any experience with the drip style heater, but hopefully others will help out here with some suggestions.

What kind of burner are you using?  Is it rather shallow, or more deep?

[geck0]

No the plans don't have to be followed to a T.. I started with a 4'' flue and a 3'' intake (it was a gas water heater). Then I changed to a 5'' flue and still a 3'' intake.. I do recommend a larger intake due to same volume of air at less velocity. (velocity causes flame-out (flame being pushed off the burner loosing heat and in turn blowing out) I just use some small metal peices to limit the intake to stop flame out when needed. A steel burner dish will hold heat much more consistently than an aluminum one. A 3/8'' steel burner should be fine (1/2'' is what i have) The height of the burn dish from the end of the intake will effect burn and flame out also. Make sure to keep the oil drip tube HIGH up in the intake pipe I would say higher than the directions because of an issue I've had at high heat, My oil drip actually became a full flame stream. It's rare to happen but it cokes up the bottom of the drip tube and effects future use/cleaning need and It's a bit unsettling when you see it.  Last but not least! The depth the flue goes into the furnace chamber greatly effects heat lose through the flue and/or burn quality and/or major soot. Fiddle with that depth to find the sweet spot mines roughly 3.5- 4'' down into the furnace too deep no heat but good burn too high extreme heat super soot. Mine is still a fickle little b@st@rd but I get great heat out of it. Now if you got through my lack of proper grammar, pat yourself on the back and good luck.