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Sky Huddleston

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since Mar 03, 2016
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Recent posts by Sky Huddleston

I have some good updates. We will be getting the heater tested to EPA standards within the next year. We have developed a ceramic lined J-tube and are working hard to bring everyone a new EPA approved rocket heater. Thank you all for your support along the way! This journey has taken much longer than it rightfully should have taken.
10 months ago

Colleen Eissens wrote:We really want a rocket mass heater, but living in a home with crawl spaces and basement so looking @ woodburner instead.  After a little preliminary planning/dreaming, decided to check with insurance agent to see requirements to avoid nullifying our fire protection.  He said that woodburner MUST be UL approved and installed per manufacturing instructions and inspected by fire inspector.
So after reading above and hearing the concerns around slow sales, the need for UL approval is a BIG deal for increasing sales.  My guess is that getting that approval rating is why the Kimberly(drooling....) or the Katydid fuel gasifiers cost $4000 , add up to a grand for installation extras.  They have made this a luxury item, basically, marketed toward the mariner crowd, but its the only rocket stove that has gotten the approval.
Any ideas as to how they achieved that could be very useful in proceeding.
A go fund me page is awesome idea, if that's what's holding this product back.
New to forum, apologies if this is rehashed info/ideas.

Insurance company's, when they say "UL approval" they mean tested and approved to UL standards by a third party lab accredited by ISO. Which we already are. We comply with any insurance policy's that permit wood stove's.

A common misconception is that UL is a government agency. They're not and they are no better as far as building codes and insurance is concerned than any other testing lab. Many company's that make wood stoves (including ours) have opted to not get it tested by UL but instead one of their competitors due to the huge cost difference. Again, as far as building codes and insurance company's are concerned there is no difference. US Stove Company, Hearthstone, Drolet,  Vermont Castings, Jotul, and many others are starting to use testing labs such as Intertek, Warnock Hersey, Omni-test, Spectrum Labs, Guardian, and many others.

UL is not a monopoly. Their listing is no better as far as insurance company's are concerned than any other ISO certified testing lab.

So to sum it up, yes, we already meet ALL building code and insurance standards for safety. That is a fact and I stand by that statement. If your insurance company has a problem with it tell them to contact me and I will show them mountains of paperwork, testing reports, approval by certified boards of engineers, and much more. Thus far I've never had to do that and I doubt I ever will.
2 years ago

John C Daley wrote:How is this project coming along now?

We're still trying to get the funds together to get it EPA Approved and Certified. We have been experimenting with refractory coatings and we're coming close to finding the right technology which will allow the heaters to without any doubt at all from anyone last indefinitely.
2 years ago

Rob Yost wrote:Hi Sky, I am very interested in installing one of your stoves. A couple of questions, do you foresee any problems burning mostly cedar?  I have access to lots of fallen, dried cedar, I am mostly worried about sparks coming out the feed tube and creosote build up.

Second, have you or anyone else played around with phase change materials (PCM) as an alternative to thermal mass?  My thoughts are to build a large steel pot to put on top of the heat riser with PCM materials inside. See for details. My goal would be to light it twice a day and keep the house comfortable.

Lastly, have you shipped any systems to Canada, and if so, what are the approximate shipping costs?

Thanks for your dedication to clean and sustainable heating!

The heater burns cedar and other softwoods like a champ. We find it burns just as good if not better with softwoods than hardwoods.

PCM's are expensive and we might look into it for our up coming hyper-model (still in the conceptual/screening phase) but thats a LONG ways off.
3 years ago

jonathan kedzierski wrote:

Glenn Herbert wrote:It is 1" thick, and the riser sections the thread discusses are 6" ID and 24" long. This thickness of this material is generally considered sufficient by itself for heat riser insulation.

I think the thread gives enough information for you to contact the manufacturer for detailed specs.

I believe I read that the vacuum formed ceramic heat risers were 2" thick, so a 6" ID would be 8" OD.

If its 6" ID and 8" OD then its one inch thick.
3 years ago

Glenn Herbert wrote:It is 1" thick, and the riser sections the thread discusses are 6" ID and 24" long. This thickness of this material is generally considered sufficient by itself for heat riser insulation.

I'm more interested in the R-value of the insulation, specifically btu-in/hr-F-ft^2 as I have a source for high strength 3300 F. rated cast refractory's that have a thermal conductivity value of about 6 btu-in/hr-F-ft^2
3 years ago

Glenn Herbert wrote:First off, I'm glad you are doing well enough with your initial model to keep the business going. The more variety in available approaches, the better, and if someone can get a manufactured version when they would otherwise not be able or allowed to build their own, that just spreads the awareness of the technology.

I don't have a more informed opinion than anyone else on minimum refractory thickness, but I think a round riser would be more durable, and probably a bit more efficient. Also, it would obviously require less material for a given system size - not an unimportant point when making them commercially. I don't think you would actually need a really heavy outer shell for the riser, as that region after the combustion zone has historically been demonstrated to have conditions not conducive to corrosion.

A 6" size would likely be easier to make as a shippable unit, and small enough to more easily find installation locations. I might consider a 6" batch box, as that is supposed to have the heating power of an 8" J-tube, so could power a larger system while keeping the smaller combustion unit size. What are you thinking with regard to connecting your units to owner-supplied mass storage? I would think there could be a way for your manufactured and listed product to have thermal mass put next to or around the exhaust without voiding the listing... is this true? If the unit you test and sell is designed to shed enough heat in itself that your exhaust could safely go up the chimney even if someone foolishly insulated the duct run (!), any kind of thermal mass would not negatively impact the assembly's safety.

A catalytic combustor would be irrelevant to a properly functioning RMH, so I don't see any advantage to including that kind of thing. I would even consider a sales point like "total efficiency and pollution reduction without a catalytic unit to worry about".

There is a thread here about inexpensive ceramic fiber heat risers, and that might be a technology for you to look at; it would reduce shipping weight, not require as much protection from shipping damage/cracking, and contain the insulation in a slender package, which could probably be fitted inside a metal shell for shipping and moving safety.

I wonder what the insulation value of that ceramic fiber is and how thick it is.
3 years ago
Hello again everyone! Its Sky again. Some of you may recall my father and I developed and are selling factory made Rocket Heaters tested to UL-1482 standards to meet building code and insurance policy compliant.

My father and I are developing a new model Rocket Heater. We have some great concepts, and not all we will share, which include but are not limited to pre-heating combustion air. However, we want to be more proactive and meeting your needs. We've learned so much along the way and will continue to do so. I finished reading the Rocket Mass Heaters Builders guide (highly recommended!) and have immersed myself as much as I can. Now we would like to consult the cumulative wisdom and experience from the members of this forum, get a feel for what you guys want to see in a factory made Rocket Heater. To everyones relief, we have decided to use a cast refractory rated up to 3300 F. for the burn tube and heat ris and have a concept to greatly increase the refractory's resistance to thermal shock, which involves reinforcing the refractory with carbon fiber. I do not believe the carbon will burn away because its incased in the refractory, but correct me if I may be wrong or if any of you have concerns! We will also use a method to have the cast refractory shelled and protected by thick steel tubing and to keep all the surface exceptionally rough, much rougher than even firebrick. However, we have some questions for all of you!

Which would you prefer, a square heat riser or a round one? Either shape is equally acceptable and easy to manufacture for us.

How thick would you like to see the refractory? Whats the minimum for strength? Remember the refractory will be surrounded by super-insulation. I just dont want the cast refractory to ever crack or fall apart. I just need to know how thick a refractory needs to be for structural strength.

Would you like to see a catalyst on top of the heat riser, or do you think the temperatures are too hot for a firecat? This will add 100 dollars to the cost of the heater.

How large of a feed tube would you like to see, 6, 7, or 8 inches? Or something in between?

We would like to go with a square body on the bell instead of a cylinder. This would give the gases more surface area and volume to release heat into the room and make manufacturing easier and smoother. Do any of you have concerns or objections to this?
3 years ago

F Styles wrote:you can tell us here. We promise we wont tell anyone. just post it here on this thread and it will be safe.

Dont worry, it will become public information in time. Hopefully within a year or two tops.
3 years ago

F Styles wrote:am i correct in saying that you want a fix for the builds you have now and a 330 SS thin sleeve insert would help mitigate a potential problem until your next build?

i think you are correct in saying the burn tube is important also and i was actually thinking of using the ceramic rings in the burn tube as well and think it would creat more of a market for you as replacement parts or upgrades.

you could sell outer insulation sleeves and inner ceramic ring upgrades for currant units if its possible?

There is no way to "fix" the heat riser because the top is not removable.

The burn tube must stay rectangular for cleaning and if the customer is using pellets.

Therefore we just want a material for the burn tube for the future, it will be an improved model of the current heater. With better machinery and higher sales volumes we expect this heater to be a great gravity fed pellet/wood stove but nothing industry changing. Right now we just want an improved version of what we have. We are developing something super secret I wont tell anyone here much about that will change the entire industry.
3 years ago