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Building an Outdoor Wood Burning Stove

02/26/2009 6:07 PM

I am wanting to build a water stove . any help on choosing the right grade and material thickness of metal for the water tank and fire box would be greatly appreciated .I am also wannting to have a oil burner on it also thank you

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#1

Re: building a outdoor wood burring water stove

02/26/2009 8:21 PM

I've built some rather efficient outdoor wood burning boiler units for use of heating a mobile jacuzi. I simply bought some thin walled oval top loading wood stoves, took some 1/4" copper tubing and tightly wrapped the entire stove with the tubing. As the water in the coils heats it rises, pulling in more cold water from the tub, creating a natural thermal syphon. I dont know what your application is, but that general design worked very well for heating my mobile hot tubs.

...of course that was only 1 part of all the redundant systems, I also incorperated a 12V pump, batteries and solar panels. Point of use propane water heater, a secondary boiler pulling heat from the cast iron woodstove inside the built in sauna. and of course the traditional 110/220V hot tub equipment. any or all of the systems could work independantly or together.

Yep, Nothing like hauling your mobile hottub/sauna through the snow to your remote campsite.

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#2

Re: Building an Outdoor Wood Burning Stove

02/28/2009 3:58 AM

If I was designing something like this, I would try and make the design power independent, that is, that it does exactly what I want without the use of mains power.

12 volts obtained via wind or sun does not count.....

I do not know if this could be interesting for you so please tell us...energy costs will only rise over the next 20 years or so, so using as little as possible right now is always a good choice I feel.....

Are you heating a house or bungalow? or what? All year round (hot water) or just winter?

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#3

Re: Building an Outdoor Wood Burning Stove

02/28/2009 8:19 AM

i have designed and built 4 outdoor stoves so far and all have been very efficiant. all have been wood fired but that is simply modified. i prefer to use pipeline pipe, makes for a heavy stove but it doesn't burn out either. if you would like a drawing to my design i would be more than happy to send it to you. Pipeline pipe is approx. 3/8" thick. i use it for both the firebox and the water jacket. This ensures a long heat up time but also means a very long heat retention time. as well the jacket being the same material. helps to reduce heat loss of the water and less insulating material is required.

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#26
In reply to #3

Re: Building an Outdoor Wood Burning Stove

03/09/2009 6:42 PM

I have built a lot of indoor wood burning stoves using well casing and pipline pipe. I would like to build an outdoor wood burning furnace. I am tired of having to repaint each spring. Anyway I would like to see your design drawings you mentioned and any other ideas you might have on this subject.

Thanks,

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#27
In reply to #26

Re: Building an Outdoor Wood Burning Stove

03/09/2009 8:30 PM

hey you can get a hold of me at keldev@mts.net if you are interested i would be happy to pass on my design for an outdoor boiler i have designed. and it is proven to work in field heating my own house. if you have ideas to add to it i would be happy to hear those always learning cause when we stop that we are dead.

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#28
In reply to #3

Re: Building an Outdoor Wood Burning Stove

03/29/2009 10:05 PM

yes please send information to larry5190@yahoo.com

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#36
In reply to #3

Re: Building an Outdoor Wood Burning Stove

11/12/2011 10:56 AM

if you would like a drawing to my design i would be more than happy to send it to you.

Please forward a copy of your Outdoor Wood Burning Stove to ejmlgm@gmail.com

thanks

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#37
In reply to #3

Re: Building an Outdoor Wood Burning Stove

12/30/2011 10:53 AM

Hello,

I'm new to this forum and I'm thinking about building a outdoor boiler. I would appreciate you sharing your plans.

Thanks,

Larry

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#4

Re: Building an Outdoor Wood Burning Stove

02/28/2009 10:19 AM

Probably you could try a TLUD Gasifier Wood Stove. You can get across to all details on Google.

These stoves consume 75 per cent less wood material for the same cooking task compared to a 3 stone fire.

Another advantage is that the stove performs best on biomass residues like twigs, etc. This supports afforestation. When you use firewood, you are generally supporting deforestation.

Lighting of the stove is also extremely easy with an appropriate starter material.

There are also several models of the stove in both categories of natural draft and forced draft.

Regards,

Rajan Philip

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#6
In reply to #4

Re: Building an Outdoor Wood Burning Stove

02/28/2009 11:46 AM

How does this design work on a continuous burn basis to heat large quantity of water. The illustrations I found via Google only showed ttiny cook stoves. The burning was done in small batches. That requires constant atention and a human presnece. While this is suitable for meal preparation,it is less suited for round the clock house heating which requires semi-unattended mode at night.

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#8
In reply to #6

Re: Building an Outdoor Wood Burning Stove

03/01/2009 11:06 AM

Although TLUD wood gasification technology is not very new, it is finding acceptance and popularity around the world only recently.

A lot of work is happening around the world, and the results are really encouraging.

There is also a model where continuous/intermittant feeding of fuel is possible.

In case you need continuous automatic feeding of fuel through several hours, somebody will have to work on appropriate designs ( which may not be existing at present ).

As you know, for such cases, people find petroleum fuels ( and sometimes even electricity ) convenient - of course at great environmental cost.

Of course, presently, most of the works with TLUD wood gasification are focussed on domestic cookstoves. But then you will appreciate the fact that there are millions of 3 stone fire cookstoves used around the world which can be changed over to TLUD technology, with benefits to everybody - including global environment.

For more details on TLUD wood gasification technology, you may contact Dr. Paul.S.Anderson at psanders@ilstu.edu.

Regards,

Rajan Philip

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#9
In reply to #8

Re: Building an Outdoor Wood Burning Stove

03/01/2009 11:42 AM

Thank you Guest for bringing TLUD cook stoves to our attention. My question about continuous feed is basd on the OP asking for information for a outdoor wood burning stove for heating a house. It seems to me your post is off topic if it is not readily applicable to a water jacketed wood boiler.

If your suggestions involve wood gasification in a water heating wood stove then some elaboration is required. Regards

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#5

Re: Building an Outdoor Wood Burning Stove

02/28/2009 11:22 AM

Insufficient detail given to produce integrated design.

The best of what is determined by the inclusion of which when how by design.

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#7

Re: Building an Outdoor Wood Burning Stove

02/28/2009 3:29 PM

A little more information is required, 3/8 is a good thickness for your fire box cut a half moon weld this to the top of your fire box, and cap the ends this is for your water. than build a concrete block building around the wood stove with the wood stove door on the outside make sure to have at least 3 foot clearance around the sides of the wood stove as well as the end, once all your pipeing is done to your half moon shaped hot water tank on top of your wood stove fill in around the stove with sand all the way up over top of the hot water tank by 2 feet. you can use this for domestic hot water as well as hot water heat. if your fire goes out you will still have heat and hot water for up to 8 hours because the sand will stay hot for quite some time. i have built 4 or 5 of these and they work well. I also have on in my own house.

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#30
In reply to #7

Re: Building an Outdoor Wood Burning Stove

03/29/2009 10:34 PM

i just read your artical.can you help i want to build an outdoor stove similer to the one you describe with sand filled around.please reply to larry5190@yahoo.com thank you.

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#34
In reply to #7

Re: Building an Outdoor Wood Burning Stove

08/15/2010 10:44 PM

can i get more information on this design please? skypony38@yahoo.com thanks in advance foer your help

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#10

Re: Building an Outdoor Wood Burning Stove

03/01/2009 8:56 PM

I built a space/hot water wood fired heater using discarded truck brake drums as end caps and a 300 mm length x 8mm thick of tubular steel same diameter as a joiner. The grate was perforated stainless steel. The flue was 75mm water pipe welded off centre in the top drum, with a circular 300mm x 10 mm thick stove top with a 75 mm hole off centre for the flue. To load wood, slide the stove top sideways around the flue. I wound 3 turns of 10mm annealed copper pipe around the centre section as a water heater.

The whole unit sat on another brake drum which had a 75x50mm hole for ash removal and draught.

This was 10 years ago and has been used most days every winter.

A friend build a similar unit with an oil dripper which worked very well.

Hope this helps.

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#11

Re: Building an Outdoor Wood Burning Stove

03/02/2009 9:14 AM

Building an outdoor wood boiler is a big job. It involves heavy welding, heavy parts and pieces, trenching, wiring, seals, controls, etc.....

If you are to build it yourself then building it in place is the best choice. Unless you have heavy equipment to move the final furnace. And you may find that heavy equipment may not do so well where you want to put it (sink in the yard etc.)

The best choice for home built is from existing steel tanks or pipeline piping (mentioned above). It lowers the amount of work involved and reduces the chance of those pesky leaks. Believe it or not it is not as simple as welding for structural purposes. Even the best looking weld with great penetration can leak. Especially outdoors where wind and contaminants can cause issues. The round face eliminates corners which can be very difficult to seal with welds. A leaking seam tends to show at it's corners even if that is not where the problem is.

The thicker the better. Both for longevity and for the heat characteristics. Think "boiler".

Many furnaces use blowers. Strongly consider draft instead. If you fire goes out your furnace will quickly turn into a cooler with cold air blown through the firebox and cooling the water in your water jacket. A draft controlled with a solenoid and a properly designed flue are less expensive to run and (from what I've experienced) run better. Natural draw can, in many cases, be adjusted simply by increasing or decreasing the chimney height.

Think twice build once. Like the measure twice cut once rule. That is how to approach the door of you furnace. The door seems to be the hardest part for most home builders. Won't seal, warps from heat, won't latch, won't even close...... these are just a few I've seen. And proud builders typically won't heed the warnings and eventually come back seeking door advice.

Sizes are important. You do not want too big a firebox even though most people assume that the more wood it will hold the less they will have to fill it. Consider that most of your heat will come from radiant transfer. You will want the sides and top of you furnace as close to the source as is reasonable. This will also have the effect of burning off creosote that will build up and insulate the firebox wall, keeping the heat from transferring.

The other size is water capacity. Again most builders think more is better. Too much water and it will take too long to heat up or your source will not keep up. Your furnace may end up staying on (fire burning at full) constantly. Nothing worse than waiting 4 hours for your furnace to heat up. Another issues is, once the water is heated up, the heat retention is so long that the fire doesn't come on for a long time and goes out. Certainly a huge heat sink for heat storage is great. But having to insulate that huge heat sink to prevent losses doesn't justify it.

Conversely, too little water and it will not keep up to your transfer requirements as you draw heat off. In an open system you run the risk of boiling off you water as well.

The suggestion of a self supportive system is a good one. With a damper system you only need a 12V or 24V solenoid to control the damper. A 12V/24V transfer pump is more than sufficient, especially if you use several for zone heating. Having a battery back-up is easy this way. And it goes well with a solar or wind system. Your controls will be 12V or 24V anyway.

I've designed and overseen the build of these stoves for a commercial company and I've helped many builders with their "red-neck wood stoves". There never seems to be one good way to build them. But there are certainly a lot of bad ways.

Guy

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#13
In reply to #11

Re: Building an Outdoor Wood Burning Stove

03/02/2009 10:16 AM

From a safety point of view, more water is better. Provided the pipes and the boiler are well insulated, so that fuel is used efficiently and no heat lost in the transfer....

Also I would strongly recommend oversized radiators, so that the achieved temperature is less important, a lower temperature will still warm up more than enough.

Do not size your radiators according to the plumbers tables....use the tables and then buy double rads, double size (that is 4 times more surface area than the plumbers tables calculate!).

Also, this will cover any points if the house is not quite as well insulated as the plumbers calculation thinks! I did that some years ago and even in the coldest winter, we only need to use water temps between 45 - 55°C, this lets our gas boiler work in a very efficient area......It also stops small children (or stupid adults!) getting scalded by the piping or rads as can happen with 80 - 90°C......also, if you are in a hard water area, the lime scale does not deposit out quite as badly either......that could only happen in the Calorifier though...

These temps are still enough for showers and baths, provided you have a suitable insulated storage (Calorifier), heated by the water from the boiler.....it also allows a fairly simple solar system to add some extra heat at a later date if required......For spring, summer and autumn, if not winter.....unless a heat pump is also used, for hot water only of course. unless sized enough for the heating as well.

The worry about not being able to heat it all up is basically unfounded (within reason of course) as the water is mainly a "transport media", it transports heat from "A" to "B"....

A good header serves two purposes, it holds extra water safely and need not itself become heated, except when needed.

A remotely operated "fire out" system, that allows the fire to be flooded with water and put out in a few seconds is not a bad idea, but it must be done remotely in some way. The boiler could be placed slightly remote from the house and then such a system is not always needed. Safety must not be ignored.....

Proper air/smoke exhaust control is needed to make sure heat is only produced when required and at the rate required......without completely shutting down as this can cause explosions if flammable gas is being produced, and someone opens the door to put wood in, letting air mix with hot flammable smoke/gas.......

I personally would design a pellets burner as I am used to the one (bought from Kalor) that is in our kitchen since 2006. It has not even burnt 2 tons of pellets in three winters!!(though it does not heat water, or our lounge, just the rest of the house Kitchen, hall and upstairs....I still have enough pellets left to continue heating till April at least!!!! Also, very easily controllable......but does need power for the fans and the igniter etc., which is probably not what you Guys want....just a thought!!

I seem to have rambled a bit, I hope that the thoughts came through.....

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#14
In reply to #13

Re: Building an Outdoor Wood Burning Stove

03/02/2009 11:21 AM

Oversized radiators work in a radiant transfer but the cost of fan driven transfer makes it excessive. In one zone I run a huge greenhouse radiator. It does transfer a lot of heat. So much so that I have to reduce it's flow or it overtaxes the system and other zones are affected. Conversely, one small fan driven transfer can heat a very large house at water temperatures around 50°C.

"The worry about not being able to heat it all up is basically unfounded" - I must disagree. I have seen many systems that are run at a lower water level than designed. This is done to reduce the run time of the furnace. It is a situation that occurs when a reasonable balance in the two transfer systems is not considered. Due to losses, some of these system were never able to get the water to temperature.

Large amounts of storage water takes a long time to get to temperature. Also a lot of energy. Holding water at temperature incurs losses. This can be overcome by storing the water in the heated building, if you have space for it. Then lost heat really isn't lost.

The idea of a fire-out system scares me. Many of these systems are run air tight. The energy introduced when water is poured onto a hot fire is immense. I would be afraid of damaging the furnace by literally blowing the door off. Worst case injuring someone. The whole idea of running an outdoor boiler is to keep the unsafe portions of the heating system outside and away from the building. If there were a serious enough reason to extinguish the fire I would let it boil over or burn it's self out.... in it's place safely away from the house.

The opportunity for a back-draft is the same with any wood stove. I've only seen it once and it's cool to watch and not at all dangerous. With a proper flue and draw system the only way a serious back-draft can occur is when maintenance is very bad and the flue very blocked and the firebox is huge. Besides, you' re a Darwin award wanna-be if you stick your head in a furnace as you open the door. With any thing like this you need to respect it and operator it properly.

On the topic of safety..... closed hot water systems are never recommended for home built systems. Besides open systems are so much easier to build and deal with and tweak.

There must be 100s of these outdoor furnaces in my area. Some commercial units but most home built. I've never heard of any issues with them other than some produce a lot of smoke or that it's too much trouble to collect the wood. I have friends on the local fire department that have them and we discuss them and they have never had an emergency call due to an outdoor furnace.

A home built furnace is a good idea if you have the time and patients to get it up and running properly. Cost of a commercial furnace (only the boiler) is in excess of $5000 (last time I checked). If your a good scrounger you can build one for the cost of welding it together.

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#15
In reply to #14

Re: Building an Outdoor Wood Burning Stove

03/02/2009 3:07 PM

I would like to answer some of your points one by one as I feel that you are seriously misunderstanding many of the points I was trying to make! Your statements are in bold Italics.....

Oversized radiators work in a radiant transfer but the cost of fan driven transfer makes it excessive. In one zone I run a huge greenhouse radiator. It does transfer a lot of heat. So much so that I have to reduce it's flow or it overtaxes the system and other zones are affected. Conversely, one small fan driven transfer can heat a very large house at water temperatures around 50°C.

The reason that it overtaxes the system is because you have never balanced the system correctly. Many amateurs do not know or understand this sadly. You probably think that the small valve that should be mounted on the outflow from the rad, is only to allow you to remove the rad without draining the system WRONG!! If you wish, I will post the proper method to use these valves in their primary use! Then you will have a correctly balanced system!

Or the boiler was seriously underpowered for the number of rads and or the house is badly insulated/drafty......

Fan driven rads are good when you only have a small place for the installation, but also require electrical energy, so efficiency drops. I never use them except where I have to.....and never in my home! Mainly in business premises where space is severely limited, or only overhead installs are possible....

Also, you are not thinking clearly, it does not matter how big the rad is. Think logically - for a particular room, you need a particular amount of heat energy to warm it up and a certain amount of energy, continually to maintain that temperature. The only difference is that a large rad makes is that you can obtain both from water at a lower temperature as well as a small rad working at high temps!! But lower temps are more easily achieved and do not stress the boiler or take it out of its efficiency band....

Remember, the smaller the rad, the higher the water temperature must be to get and maintain the temperature in the room!!! Efficiency suffers, its as simple as that.....But do not be upset, I have met well experienced plumbers that did not understand that either, so you are not alone......

In fact, I have used that question as a "trick" question to evaluate a plumber, guess what, my plumber is 66 years old, had a large business but sold it and retired and he is simply brilliant! Of 4 asked, he was the only one who knew that and he does exactly the same.....on all his previous installations and has still a lot of happy customers.....! I need him very rarely and he is now a personal friend....

A physicist will answer the question correctly by the way.....

"The worry about not being able to heat it all up is basically unfounded" - I must disagree. I have seen many systems that are run at a lower water level than designed. This is done to reduce the run time of the furnace. It is a situation that occurs when a reasonable balance in the two transfer systems is not considered. Due to losses, some of these system were never able to get the water to temperature.

The last sentence says it all, if you do not understand why, there is little point in me wasting my time telling you further!!! Remember, if your outputs are near to your inputs (energy wise), it will take an age to get up to temperature, but is also a real waste of energy too!!! I mentioned in my post that good insulation to cut losses is a must, maybe you oversaw that point. I mean both the piping AND the building by the way.....

I also have never seen a system that could be run with less water than it was designed for. Maybe I am missing something and I like to learn something new, could you explain exactly what you meant here please?

But do remember that a crap designed/installed system = crap results.....every time!

Large amounts of storage water takes a long time to get to temperature. Also a lot of energy. Holding water at temperature incurs losses. This can be overcome by storing the water in the heated building, if you have space for it. Then lost heat really isn't lost.

My home system, where each room has approximately 4 x more surface area of rads than a plumber would recommend,(therefore far more water than would normally be required!) when I switch the heating on in a room, is at the required temperature within about 5 minutes/very short time, I have never measured it with a stop watch! But as the house is well insulated, rooms do not get really cold even after 12 hours or more without heating input...I do have special wireless thermostats with computer timer control, so that rooms are only warmed when required.......my lounge goes from 21°C at 23:00 when the heating goes off, to about 18°C by mid afternoon the next day when it goes on again.....outside temps around 0°C at night by the way....they were WAY colder a few weeks ago, but it made little difference!

My heating and hot water costs are around €400 per year for gas and about €120 for pellets.....

The idea of a fire-out system scares me. Many of these systems are run air tight. The energy introduced when water is poured onto a hot fire is immense. I would be afraid of damaging the furnace by literally blowing the door off. Worst case injuring someone. The whole idea of running an outdoor boiler is to keep the unsafe portions of the heating system outside and away from the building. If there were a serious enough reason to extinguish the fire I would let it boil over or burn it's self out.... in it's place safely away from the house.

If you re-read what I wrote, I said twice "A remotely activated system", I know the energies involved, maybe you oversaw that point as well....?

Being able to remotely STOP a fire quickly, with or without damage to the boiler, is a great feeling. Insurance rarely covers damages from a home made system such as wanted here.....you might be VERY happy with the blown boiler, rather than a new house!!! Basically, with self built DIY systems you have negated your home insurance with regard to that boiler and house damage from a boiler problem!!! Even in the event of a fire/water leak from other possible reason, the insurance company may try and prove that the boiler was at fault......have you considered this whole problem fully?

The opportunity for a back-draft is the same with any wood stove. I've only seen it once and it's cool to watch and not at all dangerous. With a proper flue and draw system the only way a serious back-draft can occur is when maintenance is very bad and the flue very blocked and the firebox is huge. Besides, you' re a Darwin award wanna-be if you stick your head in a furnace as you open the door. With any thing like this you need to respect it and operator it properly.

Then you have not read or heard the news very often on that score. There have been explosions that have wrecked the stove, set fire to a house and killed and maimed the person(s) affected......

I looked on the web and found a few incidents for you, look on this page:-

http://chimneysweeponline.com/howhuff.htm

and you will read this among several other similar incidents:-

Q: I recently installed a Jotul 400 Castine wood stove in my fireplace. I used a flex pipe that extended up to the clay liner. After loading the stove for the night, I sat back with my wife to reflect on how beautiful our stove was. Just about then, the glass blew out in an explosion, spraying wood, coals and shards of glass six feet across the carpeted room. WHAT THE ****!

Perhaps you can find some links where people maintain that this never happens? Not that I will ever believe them for one second. By the way, this Guy was fully insured, Jotull is a wellknown name.....and it happened to that burner too! Not a homemade one.....

On the topic of safety..... closed hot water systems are never recommended for home built systems. Besides open systems are so much easier to build and deal with and tweak.

Agreed.

There must be 100s of these outdoor furnaces in my area. Some commercial units but most home built. I've never heard of any issues with them other than some produce a lot of smoke or that it's too much trouble to collect the wood. I have friends on the local fire department that have them and we discuss them and they have never had an emergency call due to an outdoor furnace.

A home built furnace is a good idea if you have the time and patients to get it up and running properly. Cost of a commercial furnace (only the boiler) is in excess of $5000 (last time I checked). If your a good scrounger you can build one for the cost of welding it together.

I generally agree, but not knowing the dangers is simply stupid, many people do not know the possible dangers....I was trying to make them more aware.

You do not appear to understand the technology, the problems nor the physics of such an installation.

I have the advantage on you maybe because I was designing home and office heating systems and installing them, over 40 years ago for extra money at weekends..... with no problems what so ever....some installations are still running today, with relatively minor changes - more efficient boilers mainly, or a few new rads in new extensions..... I am still friends with the people concerned as well....but no home built boilers either..... Not bad for an amateur eh?

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#16
In reply to #15

Re: Building an Outdoor Wood Burning Stove

03/02/2009 4:58 PM

Andy Germany - I believe we are comparing apples vs oranges here. I believe my references to radiators is different from yours. The systems I'm referring to are balanced from a central manifold. Much like in a floor heating system. Also, fan driven rads are the norm here. The rads (I believe) you refer to are quite rare.

The reason that it overtaxes the system is because you have never balanced the system correctly. Many amateurs do not know or understand this sadly.

My system runs great. It is balanced, I was just illustrating a possible issue. Besides, large rads are a bad idea on many counts, the least of which is the cost of the units.

Also, you are not thinking clearly, it does not matter how big the rad is.

I did say that oversized rads work in a radiant system. I was differentiating from a fan driven system where larger isn't better. Lower temperature requires a larger heat transfer area or a more efficient transfer. High temps require less area or less efficient transfer.

The last sentence says it all, if you do not understand why, there is little point in me wasting my time telling you further!!!

Wow... not sure what to say here. It's my statement. Why wouldn't I understand it?

The subject is a home built boiler. Illustrating the many issues that are involved is the point as are those specific to an unbalanced system.

We are not dealing with a rated commercial system. And I doubt the builder is going to spend the hours and money involved in monitoring it over time with different fuels to rate the BTUs. (It would be very interesting if they did.) Even the numbers from commercial equivalents has been proven time and time again to be bunk. You have to thumb it. Take your best educated guess and work from there.

...run with less water....

This one is not good. The poor individuals that end up doing this run a high risk of the water level going below the firebox and, in a case of a thin walled version, burning it out increasing risk of corrosion and boiling off the water and having to top it up all of the time.

These boilers are simply a box inside of a box. If you have too much water you simply lower the water level in the box. Not a good choice in my opinion but I've seen it done many times.

....fire-out system....

Again, apples and oranges. The outdoor boiler is a distance from the house for many reasons including insurance reasons. My insurance company is well aware of my system and my insurance went down when I installed it. This is usually the first thing I tell people to check.

Anyway... I made my point because it is very dangerous. Simple enough.

....backdraft....

I'm aware of the back draft issues with other systems. That is why this is such a good system. It is comparably safer. Especially an open drafted system like the one I use.

You do not appear to understand the technology, the problems nor the physics of such an installation.

I have to ask... do you know what the poster is asking? Do you know what an "outdoor wood burning stove" is? The "technology" is so old it's a given. The "problems" are numerous and I've run through the ritual on many of them with my system and others. The "physics"... you must be kidding. I hope your kidding....

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#17
In reply to #16

Re: Building an Outdoor Wood Burning Stove

03/02/2009 5:30 PM

You didn't answer my rather pointed question about water reduction directly I feel. As you originally wrote, it was a "fix" for some imagined water heating problem, now its dangerous - as it was in the beginning and still is......you have a way with bending words to suit your point of view.....

Running with less than the designed amount of water, which is a full system, is and always WILL be very dangerous....but at least you now agree with me on that point. I suppose one should be thankful for small mercies....

You also were unable to refute fully many of the rest of the points I made and some you seem to have ignored and others not understood....par for the course I suppose......

One point further, I wonder if the original poster has spoken with his insurance company and got a quote with regard to his proposed stove.....it would be most interesting to hear what was said.....it must be done as NOT declaring makes one liable.....

I can see I am "flogging a dead horse" in trying to make you fully aware of the basic inaccuracies in 90% of what you originally wrote.....I hope that nobody ever lives to regret anything you mentioned.....including you.

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#19
In reply to #17

Re: Building an Outdoor Wood Burning Stove

03/03/2009 8:38 AM

My comment: "These boilers are simply a box inside of a box. If you have too much water you simply lower the water level in the box."

If I dumb it down any further I will have to write it in crayon. And I never said it was dangerous. You clearly have no idea what you are talking about.

Unable to refute??? When you started abrasively blabbering on about the valves on an unrelated specific type of radiator, your comments lost any validity.

I would not be surprised if the posters insurance carrier has similar policies as mine. The bigger issue is local legislation.

Obviously you are in no position to make anyone "aware" of any inaccuracies. Your the crazy person that suggested injecting water into a live furnace?!?!

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#21
In reply to #19

Re: Building an Outdoor Wood Burning Stove

03/03/2009 12:25 PM

Mr Devine (?),

Andy G. has been here a long time and helped a great many people on many subjects. He is a "very safe" person in all respects and did mention to use "remote control" in the original post, so he knew full well that it could be dangerous being close, so why keep picking on that one single point? Or did you not read fully thru before posting.

Or maybe its because there was little else to critic. picky picky!

As he later pointed out, if things go really wrong an "instant" shutdown might be quite attractive!!

It appears you suffer from the N.I.H. syndrome. Ask me to explain if the term is unfamiliar to you :-)

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#22
In reply to #21

Re: Building an Outdoor Wood Burning Stove

03/03/2009 1:30 PM

My intention "guest" was not to initiate a confrontation on the forum.

We can not, from the comments on the forum, understand why Andy became so abrasive. It certainly has escalated quickly. It was quite entertaining.

Sure Andy and I were jabbing each other back and forth. But I think it is mostly from miscommunication. We have opposing positions. I assume it's left at that. I hope Andy doesn't read more into it. It's a comment on a forum.

One single point? Little else to critic? Have you read the posts? If it seems pronounced it is the only point that I disagree with. It is a home built unit. How far away is safe from a high energy steam canon? Or from the debris of the shattered door. I've seen similar releases of energy and, as I posted, "it scares me".

NIH. You see NIH? Now that is interesting. How so? (no sarcasm intended) I suffer from a lot of things. MWC syndrome too (married with children).

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#23
In reply to #19

Re: Building an Outdoor Wood Burning Stove

03/03/2009 1:48 PM

I would like to regret my posting #19.

When comments get to this point one must step back.

Reaction is not the best action.

Andy Germany, and other members, please excuse any offense.

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#29
In reply to #11

Re: Building an Outdoor Wood Burning Stove

03/29/2009 10:25 PM

hello i need help designing an outdoor wood stove.please reply to larry5190@yahoo.com

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#32
In reply to #11

Re: Building an Outdoor Wood Burning Stove

07/21/2009 11:29 PM

could you please send me directions on how to build one?

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#12

Re: Building an Outdoor Wood Burning Stove

03/02/2009 9:27 AM

To be more direct in answering your question.

Many consider stainless is the way to go. You are better off using the money to get a thicker plain steel. A proper design is the way to avoid rusting out. Not spending your money on expensive materials.

Thickness. As thick as you can get. My suggestion for outer jacket is 40" pipe with a 1/2" wall. Firebox is a 3/8" thick wall.

For an oil burner I guess you could mount a fancy injector system on the door like a system from a modern furnace. I can't see how it would transfer heat without a fancy firebox. I've heard of drip systems used which run a tube down the flue and into the firebox. I've considered trying this myself to burn waste oil. Google waste oil burners and you will see what I mean.

If you want to have an oil burner as a back-up or optional source you should consider a separate oil boiler. Fuel and heat transfer requirements just seem too different to me to make a single unit efficient. Especially in heating a large volume of water.

Guy

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#18
In reply to #12

Re: Building an Outdoor Wood Burning Stove

03/02/2009 5:41 PM

instead of all the fancy hype , a couple old non leaking heater cores from an old bus or semi, mounted in the heat plenium, of your furnace, i am guessing you already have a furnace in place just costs too much to run... using the furnace fan and duct work to move the heat trough your house. as for dampers i already mentioned a damper, they are usually 24 volt. as for a pump that is expensive they are about 400 to 500 dollars for a good cartridge pump this is to be mounted in line on the hot water line just before the rads. one stoking of the furnace every 12 hours is usually good worked in a manitoba winter anyway. and yes you need piping 1" water line works good and then you aren't playing with adapters and bushings as much. bury the water lines about 2' deep and surround them with an insulated box, i use standard construction styrofoam insulation for the box. and fill inside the box with sand and back fill with dirt or what ever you want to use. as for stainless steel, better get the engineer out to stamp the thing right away too alls you need is 2 gallons of boiler conditioner added to the water and corrosion is kept to a minimum. some guys swear by a 50/50 mix with water and R.V. antifreeze, thats good tooo then then first cold snap you have no worries about frozen lines the first fire of the season.

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#20
In reply to #18

Re: Building an Outdoor Wood Burning Stove

03/03/2009 8:54 AM

Bus heater cores (and similar) have been used in many installations I've seen and seem to work well. Better than the auto coolant rads that many use.

The commercially suggested pump that most use in this area is about $170. It's just a small circulation pump. I've tested a few and the one I stayed with was an inexpensive 1" water pump from Harbour Freight Tools. $35 and it's in it's 3rd season and running strong. At that price I've considered pluming a second one in permanently as a back-up.

The underground piping is very expensive for the commercially suggested product. I spoke with one farmer that installed his furnace 100 ft from his house and paid $24/ft for the piping. Installation and fittings were extra. I did a similar installation to yours and it seems to work fine.

I did have a freeze up once and it was not fun. An early cold snap caught me off guard. Nothing burst but it took a couple of hours to unfreeze the pipes where they enter the ground.

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#24
In reply to #20

Re: Building an Outdoor Wood Burning Stove

03/03/2009 2:11 PM

i think i paid about 10.00 per sheet of styrofoam, and 50' from the house every 8 feet required 2 sheets of insulation. as for the water line i paid about 2.00 a foot and the back hoes was in and out in 2 or 3 hours. as forthe circulation pumps i woul;d still pay the extra for the cartridge pump one is going on year 15 and the other year ten. and all that and all with the hardest water you can imagine running through them. the year 15 has never had conditioner or anti freeze just the well water.

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#25

Re: Building an Outdoor Wood Burning Stove

03/04/2009 5:13 PM

Wow! Quite a bash eh? Not a war really just a lot of smoke you guys put out

The old old wahy is to use masonary and with very good result from DYI's generally. Insulation of course is key, dangers caused by pressure is seldom heard of.

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#31

Re: Building an Outdoor Wood Burning Stove

04/01/2009 10:00 AM

Thanks to everyone for all the good information. It has given me a lot to think about. Mine will be 125 feet from the house built into the side of a steep hill. It will be housed in a concrete block enclosure. I wish it was installed today as it looks like the dead of winter out there this morning.

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#33

Re: Building an Outdoor Wood Burning Stove

01/07/2010 1:15 AM

If you heat your home or use hot water, you're using energy to do it. Most of us rely on natural gas, fuel oil, or electricity to get the job done. another option that could save you a lot of money is burning wood in an outdoor boiler. Outdoor wood burning stoves are becoming more popular as people get more interested in doing things at home and for less money. Take the time to investigate your options and learn what the efficiency rating and construction method for a given outdoor boiler is. Consider the type of fuel you'll use, too. One good bonus of these stoves is that they usually burn scraps and waste wood just as effectively as good quality firewood, as long as it's properly dry.

Internet retailers often have a larger supply of boilers than local sellers. They are cheaper to run than many other methods of home heating, and they can be more environmentally friendly, but you have to know how to use them. You just need to find the right one.

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#35

Re: Building an Outdoor Wood Burning Stove

08/17/2011 9:48 AM

I have been looking into Outdoor Wood Stoves. I can not wait to get mine installed!

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