Alan Lamborn

Thanks for the detailed write up Dale. I have a couple of Stihl chainsaws and have wondered about their long reach products. These postings are very informative being able to see the work you are accomplishing with them. I didn't even know they made that harness for these.
AL

Anyone else have connection issues to their site? I was able to read the FAQ last night, but since then keep getting # 500 Internal Server Error for any of their pages. The DVD's look like they should be great, not sure how I missed the kickstarter.

Sue,
You still have plenty of time to plant potatoes if you like. I'm just a little further north of you and the only crop of potatoes I planted in mid July 2014 did great by the time I dug them in October. Take note of the other good suggestions you are bound to get here, but don't cross off your potatoes yet!
AL

Elizabeth,
Here is a thread at Permies that you should check out. RMH in floor heating for a yurt, just what you were looking for.

https://permies.com/forums/posts/list/40/5937

Welcome John,
Here is a link to another recent discussion of using radiators to heat hot tub water: https://permies.com/t/44409/rocket-stoves/Rocket-stove-water-heater-radiator

If you search the forums there are many other discussions on this topic also.
AL

Hello Stephane,
I just remembered a discussion of a stove that may be useful for you. Please check the following link: http://donkey32.proboards.com/thread/1023/accidental-discovery The user has a portable "Walker" stove and their heat riser had tipped over after a move. Not surprisingly, they found that the angled riser directed the heat to the location it was pointed at. The surprise comes from the finding that the stove appeared to burn just as happily this way as with the riser straight vertical.

A few experiments based on that finding could help you shorten the burn chamber closer to more "normal" dimensions. Which should help counter the backdraft issue and still get the heat directed to the other side of the wall. Good luck!

AL

After several tries unsuccessfully, I tried the instructions for clearing the cookie cache on Chrome (OSX). The downloaded file size changed, but still could not open the pdf due to corruption. I switched to the stock OSX browser Safari and it downloaded an uncorrupted pdf the first time. Yea!

Not sure why that worked, but thought I would share my experiences for others. Thank you Cassie for all you efforts!!!
AL

(EDIT: spelling )

Hello Stephane,
Your arrangement sounds quite interesting. By chance do you have a picture of the setup? I think that it would be important for us to understand the modified burn chamber and the situation driving that. I'll second skipping the secondary air intake to the bottom of the feed tube. It will encourage the feed tube to act more like its own chimney at the beginning and the end of the burn, when the heat pumping action is the weakest. Thank you for sharing your work on RMH's!
AL

I think consequences are the only teachers that Jerry will learn from. I've let my kids learn a lot from exploring, trying stuff, and most importantly dealing with the results. Keep in mind that I did work hard on their understanding of safety and what to do before turning them loose.

As for a permaculture solution to Jerry, Hugelkultur comes to mind....

Gino,
I hope you father gets better soon. The pictures are very helpful. You have good welding skills! I can see why you chose metal for the prototype. As mentioned above, an insulated burn tunnel and the lower part of the heat riser will degrade metal quickly in a "permanent" installation. But back to our discussion of getting your prototype rocketing!

I understand why your feed tube has the opening increase to 13". It's the shape of the preformed metal that you are re-using. If this larger 13" diameter starts to close to the combustion zone, the slower air movement in the large diameter area will make it easier for the fire to creep up the sticks/fuel. Typically the feed opening will be keep the same CSA as the burn tunnel along it's length. This will keep the air moving and cooling the fuel so the fire stays put in the bottom.

The first picture shows a small hole at the bottom in the smaller diameter area of the feed. I believe you had described this as an air intake. This may not be having the desired affect for your prototype. By having this opening it greatly lessens the flow of air coming down the feed. In fact, it makes it easier for the feed opening to act as a chimney leading to the smoke-back you have seen. Combining this with a tight fitting lid over the end of the feed opening has the potential of actually being dangerous. Let me explain the possibilities. With a tight fitting lid, as the fuel is consumed unburnt gasses and heat start collecting in the feed opening. If the unburnt fuel gets hot enough it could start outgassing. Combine that with enough heat and it only needs a breath of fresh air to ignite, like taking the lid off of the feed opening.

All is not lost. A simple two stage test can check this theory. First, block off the additional air intake at the bottom of the feed so the air will be pulled in past the fuel. You could try a small fire to test just this change. Second, if you have some additional duct/piping in the 5" diameter range, same CSA as burn tunnel, stick it down into the small diameter section of the feed opening. Also limit the length of this test feed tube to 1/2 - 3/4 of the height of the current feed opening.

These steps should change its behavior dramatically, even with the 5 foot test chimney. Try this along with some of the other users suggestions and see if the rocket comes alive for you. I look forward to hearing your results!
AL