Caleb Mayfield wrote:My feeling is weather, and possibly wind, is the primary culprit.
If I load it up with larger stuff off the bat, or less fat wood it takes longer to get warm and I struggle to get it up to 500 F. It gets warm and gives off the heat we need, and looking at the chimney it's burning clean, just not as well as a good hot start.
Just a thought.
thomas rubino wrote:Staci; If it is weather, then you might try making your chimney taller outside. I know the costs involved with that, to do it right. If needed, you might just try and stick a piece of plain stove pipe on top and see if it has an effect. (remember it will not be insulated ) If it seems to work and you can't afford a new piece of insulated pipe, then insulate your own. Ugly but wrap it with insulation and slide a larger pipe over top. Later if that solves your problem you can save up for a shiny new metalbestos pipe.
Graham Chiu wrote:Do you have weather data for your immediate region? In particular wind speeds? If not, can you measure it?
Staci Kopcha wrote:
Thank you for the suggestions!
Maddening enough, there was NO wind! Crazy. They issued the burn ban due to the stagnant air. I could understand high winds being a factor, but none..? Weird.
I appreciate the comment on using the smaller wood straight off. I have noticed that too, when I am impatient to not want to babysit with smaller pieces, and instead add thick pieces... impatience does not pay off in best heating results.
Mark Tudor wrote:How big is the gap between riser and barrel? A normal burn with typical gap should be getting barrel top temps several hundred degrees hotter than 475 I think. Also don’t forget that normally it takes heat about one hour to travel through one inch of cob. So if you have say 5 inches on top of the bench those temps will take some time to increase. Wouldn’t a taller chimney cause even more trouble, if the issue is too strong of a draft pulling the exhaust through the mass too fast for full heat transfer?
Staci Kopcha wrote:Hi Graham,
It is hilly terrain in my immediate area. House is just nearing the top of a rise.
Got this from an on-line topo map:
Elevation: 136m / 446feet
Thomas Tipton wrote:Hi Staci.
I've been following your build with much interest. In regards to your RMH troubles, I just wanted to weigh in with my two cents. First, I find it odd that you have trouble with the draft not being strong enough to keep the fire from creeping up the feed tube, but then we are entertaining the idea that draft is so strong it's preventing your mass from heating up.
From what I have seen I would surmise that you need more space between the top of the riser and the barrel lid. While two inches of clearance should be enough, I just have a hunch this area is the point of restriction that is keeping your dragon from performing to it's fullest. Maybe others can weigh in on this?
Good luck to you in resolving this issue. I'm very much impressed with your accomplishment thus far.
Staci Kopcha wrote:RMH frustration.
At this point, I want to smash the second bench (after the "L"), as it is never very warm or retaining much heat. I suppose it would mess up the system, because there would not be the ideal duct length, BUT, honestly it is pissing me off. (Pardon my phraseology) The temp of the outside corner of the "L" read at 64F, 70-87'F is what the rest of it runs.
Perhaps I am under a misapprehension in that the second portion of the bench is supposed to be warm...?? What is a typical temp? I will see if I can find it anywhere.
Maybe my expectations are out of wack??
Staci Kopcha wrote:RMH frustration.
Today it has been running for 4.5 hours. I used a mix of fir and madrona wood , with odd bit of cherry, alder, and maple - all very dry.
Chimney pipe inside the house at the very top is at 107F. First portion of bench is slightly warm to sit on, second portion cool.
Temps today were cold, and now 32F, snow is predicted.
Wind is nearly zero. Pressure is "29.41 in"
thomas rubino wrote:Good Morning Staci;
I suggest that for now, you put a candy thermometer in your chimney. Start monitoring your true gas temp rather than pipe temp.
I have been learning how different gas temperature's are from pipe surface temps. And how rapidly that temp changes. It is a true indicator of rocket performance.
I can't renounce my name. It's on all my stationery! And hinted in this tiny ad:
Getting ready for the Better World Book kickstarter - February 2019https://permies.com/t/99513/ready-World-Book-kickstarter-February