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whacker, great explanation.

Does a RMH need to have the exhaust cleaned more often? I thought that if the exhaust wasn't hot enough on exit, then there would be significantly more creosote build up?
I am not an RMH Doctor(But I did stay in a Holiday inn express last night) But what I think happens is that because the secondary burn chamber gets soo incredibly hot the ability for creosote build up is greatly reduced. Paul also expounds on that in the podcast. There are clean outs built into the system but because the burn is so full the ammount of ash is lessened also. I just saw a video of a lady's RMH and she shows how much ash she cleans out (at about 3:50) http://www.possible.org/a-look-at-chelle-lindahls-rocket-mass-heater/. Watch the whole video it explains how it works.
 

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I installed a nat gas, non vent fireplace in my living room. We fire it up (like a bbq grill-sparker or light pilot), crack a couple of windows, place a CO detector on the mantle(battery powered). Warms my 1200 ft ranch perfectly. On a -10 deg night we maintained 68 degrees, cycling the burner. No electric needed.

Note: We shut it off when turning in for the night. Safety first.
A 5 day, no electric week prompted the install. Ice storms closed roads, 30 in of snow with 3' tall drifts, used the stove burners, same air exchange rules(open couple of windows) battery CO monitors all over house. We had plenty of preps, no sufferage till TP started to run less than 3 rolls in stock. Power came back on, all's well.
 

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How high are the ceilings in the house ?

A 1" insulated dropped ceiling tiles - even if only 8" cuts "X" amount of square feet to be heated --
 

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Thermal mass is a good thing to a degree.

I have found that with my wood stove it puts out plenty of heat if I keep it going, and it does keep the house warm for 4 to 8 hours if I build a good fire and then let it die out, but to keep the house warm longer some more thermal mass would be good.

As pointed out though, there is no magic to it - there is balance and good overall design of the whole house and heating systems. They have to work together.

I grew up in a poorly insulated (as in NO insulation) poorly designed farm house built in the late 1800s and it was a struggle to keep any room warm in the winter, much less every used room comfortable (it had an upstairs that we did not use at all and that was all closed off - but we lost a lot of heat through the ceiling).

The people who built that old house also later (1940s) built a nice brick house across the road which had good thermal mass, a hot water boiler (diesel) with radiators in each room. That house was always warm in the winter even though it had no insulation and the heating system was crude compared to basic systems in houses today.
 

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Matt,

I see what you mean but I was just listening to a podcast on my way home from work that addresses many of your concerns. Paul Wheaton is one of the guys that are on the forefront of getting these types of systems more widely used for space\people heating. http://www.thesurvivalpodcast.com/wheaton-rocket-heating. In it he describes that the effeciency rating for wood stoves is skewed because it is just a marketing ploy for you to buy this or that wood stove. ...
Sorry, but that is not how the EPA or engineers rate stoves. It is not a marketing ploy. Wood has a BTU rating based on calorimetric burn tests. It does not matter if you burn it faster or slower. The effiency of burning for a wood stove does take into effect the amount lost to the chimney.

Incomplete combustion would end up with coals (carbon). Those coals would have BTU's left unburnt. A rocket stove can not put out more than what it has in the way of wood to burn. Capturing the waste heat in the chimney has been tried with many systems over many years. It is the principle behind stone/brick fireplace chimneys. A free standing wood stove does a better job regardless.

Thermal mass requires BTU's to warm it up as much as any BTU's it can radiate. Thus what is known as soak temperature. If your room has a large thermal mass in it, it actually will take a initially higher rate of BTU's supplied before the room heats up. The advantage to thermal mass is that it evens out the heat distribution over time.

It sure would be interesting to see a heads up comparison between a modern wood stove heating a space and a rocket mass stove. I expect that the wood required would be close to the same. (In reality I expect the modern air tight wood stove would beat handily the rocket stove.)

ETA: I thought up a notion to try to help explain thermal mass and why it is not what some folks think about it. Turn on your cooking stove (gas/electric) and set a metal skillet on it. How long does it take to reach the temperature of the heating element? Now take a pot filled with water and set it on the stove. How long does it take for the water to heat up til boiling (water only heats to boiling temperature)? The pot with water will take considerably longer to heat up. Take each off the stove and time how long will each take to cool back to room temperature? The water filled pot will take longer to cool. This is how thermal mass works. There was no magic gain of heat from the water filled pot. It is just radiating the extra BTU's that were used to raise it to boiling temperature.
 

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Incomplete combustion would end up with coals (carbon). Those coals would have BTU's left unburnt. A rocket stove can not put out more than what it has in the way of wood to burn. Capturing the waste heat in the chimney has been tried with many systems over many years. It is the principle behind stone/brick fireplace chimneys. A free standing wood stove does a better job regardless.
I get it man you are skeptical I would be too. I have been following Paul for a while now and the guy has his head on straight'ish. I think you are missing the point of a RMH. The heater is designed to heat spaces and people and capture as much heat as possible to be held in the mass of the built unit. All the while utilizing a fraction of wood to do it due to the ammount of heat pulled from the burn itself. Use your boiling water analogy how much of those BTU's are radiating outwards and heating the air around it vice the pot and water. In the same mannor (Dont do this) if you were to put your hand infront of a standard wood stove vent you would likely burn yourself not so with a RMH there are many videos you can pull up on the net that show this. Comparitively speaking even a high effeciency wood stove uses CORDS of wood to heat the typical home in a cold climate whereas the RMH utilizes twigs and or branches.

I mean we can both take a trip from San Diego to New York you can drive a Corvette and I can drive a Prius(I would never but I'll take the hit on this one) We can both get there, you could get there faster and look better doing it, but if the goal was to get there the most effecient way possible the Prius would win(Yeah I said it the Prius is the winner). The goal of RMH's is to be as efficient as possible while utilizing the least ammount of local materials and cost as cheap as possible. Listen to the first quarter of the podcast or the video I posted from possible.org he gives a good argument for RMH's
 

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Ways to heat that is off grid:
Fossil fuels (propane,kero,gas,diesel,natural gas,Butane)
Coal (oops this is fossil fuel and should be listed above).
Methane (does this fall under fossil fuel?)
Alcohol (Burning it if course)
Wax (Burning it of course)
Solar power (electrical or warming of air or water)
Battery power (electrical heat not on grid produced and stored)
Generator power (by engine,hydro,wind,electrical not on grid)
Geo Thermal
Steam (I'm sure it would be made by another item already listed here)
Nuclear (not Available to the general public, but hey it's a form of heat)
Wood and dried plant vegetation. (Burning it of course)
Scavenged heat from an internal combustion engine.
Animal manure that's dried out. (Burning it of course)
Various papers and other garbage. (Burning it of course)
Spontaneous combustion through rotting matter.
Creating friction between two surfaces.
Body heat (don't confuse this with the above heat source);)

Did I miss anything on different ways to heat a house?
 

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The sun will rise
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I am an expert in solar heating and highly recommend you read the Solar Greenhouse Book by McCullagh.

There are many ways to heat a house, another is to learn to construct a Kachel Offen.
 

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... Comparitively speaking even a high effeciency wood stove uses CORDS of wood to heat the typical home in a cold climate whereas the RMH utilizes twigs and or branches.

I mean we can both take a trip from San Diego to New York you can drive a Corvette and I can drive a Prius(I would never but I'll take the hit on this one) We can both get there, you could get there faster and look better doing it, but if the goal was to get there the most effecient way possible the Prius would win(Yeah I said it the Prius is the winner). The goal of RMH's is to be as efficient as possible while utilizing the least ammount of local materials and cost as cheap as possible. Listen to the first quarter of the podcast or the video I posted from possible.org he gives a good argument for RMH's
You still are not understanding that efficiency can not be that much greater for a Rocket stove. Your analogy using cars are not comparing the same energy requirements. The cars may both burn gas but they weigh different, accelerate different and the Prius has braking regeneration that captures some of the energy used to decelerate. Incidentally, Prius at constant highway speeds are not all that good at gas millage, they need stop and go driving to gain that braking recapture.

Regardless of what someone tells you on a podcast it is math that tells the final story. If the math does not add up, than the story is wrong.

The goal of a small rocket heater is to cook food. A large rocket heater is simply inefficient means to heat a home. Take for instance the idea that it draws in more oxygen in order to burn hotter. That oxygen has to be drawn into the space needing heating and it has to come from outside the heated space. Unless that air was ducted directly to the rocket stove it would act to cool the space needing heating. Thus no gain for having a hotter burn.

It is the old story of Thermodynamics.
 

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You still are not understanding that efficiency can not be that much greater for a Rocket stove. QUOTE]

Matt,

That is where our wires were crossed. There is a great deal of difference between a Rocket Stove and a Rocket Mass Heater. If you are comparing the "stove" then yes I am way off base in that regard. But the Rocket Mass Heater does not work the same way as a simple L tube Rocket stove like the Eco Zoom or the Rocket Stove like the Stove Tec version. Those just concentrate the fire with updraft to heat an element\pot. If you take a look at the below pictures and maybe listen to the podcast a little then it might clear it up a bit more. I am sorry for the confusion.



The RMH works on a totally different combustion principle. The inital burn of the wood and then the super heated gas secondary reburn that radiates outward from the barrel and then once thermally banked in the mass of the seating area released slowly much longer than the initial burn radiation. The thermal updraft creates the rocket like pull over the fire through the system. The beauty is the burn of the wood gasses just like in a more complex wood gassifier system just not cooled down before the secondary burn. I have included some pics so I can be as informative as possible. Pictures show it better that I can explain it.



Simlpy Done


Or a little bit more decorative.
 

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If anyone has ideas that I don't post below, I'd truly appreciate reading them!!!

... [Snip] ...The idea is to get the room to a reasonable temperature and then stop heating. Cover the window with something that will hold extra clothes, linens, whatever to insulate the window. Like nail/staple a blanket over the bottom 3/4 and stuff clothes in the window well...
I'm surprised this hasn't been touched on more. Heating a house is one thing, but it's all too easy to neglect the quick cheap cheats to keep it at temperature. Upgrading to good thick curtains is a whole lot cheaper than upgrading to the super efficient windows, and a couple tubes of caulk is even cheaper still. Winter is coming, might as well give your house a once over and knock a few bucks off your heating bill.
 

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Hey everyone, wanted to see what ideas are out there that could be useful in heating my home when the power goes out. I live in a smaller bi-level house with no fireplaces and so-so insulation in Northeast Ohio, and my biggest concern is the power going out for an extended period of time in the middle of winter. What would you suggest as alternatives to keeping my home warm without electrical power given this information?

Thanks!
Same here! In an apartment (bottom floor of a split level home) that's on electricity. I bought a portable propane (camp) heater, but am also going to get a kerosene heater as well. Have propane, kerosene lamps, candles and glow sticks (lots of them) for backup light. I also have a propane camp stove for cooking if needed, and can make up a rocket stove outside my door if needed. Just make sure you have a little ventilation to be on safe side indoors. :space:
 

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I'm surprised this hasn't been touched on more. Heating a house is one thing, but it's all too easy to neglect the quick cheap cheats to keep it at temperature. Upgrading to good thick curtains is a whole lot cheaper than upgrading to the super efficient windows, and a couple tubes of caulk is even cheaper still. Winter is coming, might as well give your house a once over and knock a few bucks off your heating bill.
I also use those "worms" thick round cloth lengths at bottoms of outside doors inside house to keep out any little gaps in wind drafts. They add up.
 

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Prep before it happens. Improve your insulation situation. Weatherstrip doors. Add more to the attic and walls, caulk windows and add layers of plastic sheet to them. (If you are using some king of aux heating system you may need to keep some windows open a crack for ventilation.) Insulate under the floor and add lush carpeting. Add insulation to you by wearing warm clothing. Add insulation to the sleeping area with every blanket and sleeping bag you own.

Pick one room to keep warm, preferably minimum window exposure. Pull window shades and curtains. Stay off the floor.

Even without electricity, gas is usually available for cooking. It is not considered safe to use gas ovens/stoves for home heating. If you do so you must keep a window open and keep an eye on it. Fire danger and carbon monoxide/dioxide risk for continuous unattended use.

Never use a hibachi/bar-b-q or similar for heat or indoor cooking. Carbon monoxide will knock you out and then kill you. More people die from this than from the cold during outages. Getting enough ventilation into the house to be safe negates the heat gained. Open flames MUST have a chimney for draft. You don't have one. Turning on a gas burner long enough to heat food is OK.

Having an emergency generator you can run a few hours a day to run your furnace or an electric space heater is a good idea.

Propane catalytic heaters are good for a short term option until you run out of propane. Again, for use in vented areas only. They produce carbon dioxide which can be dangerous in higher concentrations.
 

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....
Matt,

That is where our wires were crossed. There is a great deal of difference between a Rocket Stove and a Rocket Mass Heater. If you are comparing the "stove" then yes I am way off base in that regard. But the Rocket Mass Heater does not work the same way as a simple L tube Rocket stove ...
I understand the approach is different between the two. I also understand that you can heat with a candle a totally insulated space. The proponents of rocket mass stove are claiming a efficiency that simply is not possible. Lets go to the math:

A 80% efficient wood stove uses about 80 pounds of wood a day to heat a house.
A 100% efficient rocket stove (and they are not that efficient) would require 60 pounds of wood.

A 25% gain in efficiency between the stoves (100 is 25% bigger than 80) is not going to allow you to burn a few twigs for a few hours to heat the same insulated space.

Even if somehow you could double the efficiency for the rocket stove you would only halve the wood requirement. This is why regardless of nice pictures of RMH's, the story is incomplete.

At any rate I wonder what happened to the OP. He has not responded to his Thread.

Thanks for the response and friendly debate on RMH, Whacker!

ETA: You know, the more I look at the image for how the RMH is supposed to work, the more I doubt it can. I fail to see how a draft could be generated by normal thermal convection. The image has hot air from burning falling down in the drum before venting sideways. Smoke from burning the sticks would be more likely to rise straight up into the room. Heck even my high efficiency (83%) wood stove has trouble getting draft on days that have a temperature inversion or total calm. I really smell smoke on the whole concept.
 

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With Kerosene and Propane heaters do I need to worry about running them inside and killing everyone in the house from carbon monoxide poisoning? That's the only reason I hadn't ever considered them. I appreciate all the quick replies!
Yes. You should have at least one and preferably more battery operated CO monitors around, and not run heaters at night when everyone is asleep. The instructions for propane and kerosene heaters stress sufficient ventilation during use, as for instance by opening a window. They can be life savers if used properly; life takers if misused.
 

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Mike K,

THANK YOU for teaching me that there was a thank you button! (I've only been here a month or two, consider myself "alert", but had no idea!) What a wonderful feature for a forum!

(My first thank you was thanking you for pointing this out... (Totally laughing at myself here!)
 
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