Question about vent on antique coal stove

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Some people are saying that since it’s not fully cast iron that I risk damaging the metal and ruining the stove. Do you agree?
If any part is glowing red then it is too hot, but these tin stoves stood up pretty well to the temps you are seeing.
 
In this thread, people say that their coal beds seem to burn between 1000-2000 degrees F: https://coalpail.com/coal-forum/viewtopic.php?f=67&t=488

Why would a wood fire burning cooler than that be dangerous to the stove?
The coal bed is typically in a refractory, firebrick or cast iron chamber inside at the lower part of the stove. This protects the outer jacket. The surface temps you are seeing are not too high. Keep them under 750º and it should be fine.
 
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Everyone keeps recommending I burn coal, and I’m willing to try that as an experiment, but here’s the problem: I can’t find anywhere to buy coal here. I live in Fayetteville, AR. A search for “coal for sale” shows me two options: Tractor Supply, which sells a 40 lb bag of nut coal for $10 (including tax), or coalforsaleonline.com, which sells a ton for $1,200. Those are my only options.

From what I’ve read, people are saying they go through about 50 lbs a day. Let’s assume I use 40 lbs because my house is small. That’s $300 a month, which is more than my highest cost for electric heat. Plus the cost and hassle of driving to the store, buying it, bringing it home in my car, etc.

Maybe I need a modern stove. But I don’t have one, and I can’t afford one right now, so its more helpful to discuss whether I can do anything to improve my wood burning experience.

Not trying to be grouchy, just trying to explain my situation. I really appreciate all of the help and information.

You don't need a modern stove, you need a wood stove.
I'm in the same position as you with acreage of woods, so I have to weigh the work factor taking lots of time for wood or buy coal and give myself a break. About every 3 years I go coal, since storms and dead trees have to be cleaned up anyway. I never cut live trees unless they are a problem. I do have a dedicated Hitzer coal stove with gravity hopper feed, and miss using the Kitchen Queen with oven using wood, so many times I'll fire the wood stove when baking and idle down the coal stove for a day or so. You "can" burn wood in any coal stove, just not efficiently. You can't burn coal in a wood stove. They are built differently for different fuel.

With that small stove you may only go through a little over a bag a week. I go through one coal hod a day with normal temps around 32*, two buckets a day in the single digits and below. Yours won't hold more than 1 bucket. (coal hod) Probably only a half a day.
5 weeks per 6 heating months (here) would be 30 weeks heating, so your cost at $10 / week, is more like $300 for the entire season. That should be about right since I can burn $440 worth here a season in a much larger stove. (At least 3 times the grate area) January and February we don't go much above freezing with rare 0 degree nights.
If you try a bag, you will find out how long it will last and have a better estimate. "Nut" is Chestnut, which is the size you want.
I have heated 1800 sf. in NE PA. for many years, and two tons a year is average. A mild year we only used 1 ton, long cold winters 2 1/2. It can vary that much. That is our only heat source. We light it early November and let it go out late April. 20 years ago it was 100 a ton, couple years ago it was 220 a ton, a little more now. Coal follows diesel fuel prices because it take diesel to mine and haul it, but is the most stable priced fuel you can buy. For those of us that live near coal sources it's a no brainer, just like living near a pellet mill where that fuel is abundant.
It also needs to stay below 40*f for a 24 hour period to light and maintain a coal fire unless you have a very efficient insulated chimney.
There is a learning process to burn coal. Don't expect to go "one match" an entire season learning the first year. We only shake and empty ash in the morning, and shake and fill at night, but your smaller stove will need more attention than twice a day.

If you continue wood, depending on chimney, you will need a damper in the stove pipe to control draft. (very cheap) A pipe damper is not a stove control, it is a chimney control that affects the stove. Used properly it will prolong your fires. Used improperly it will create creosote.

If you burn coal, you should have a barometric damper in the pipe to control draft. (not using the manual dilution damper on stove) Coal requires a much more controlled draft, so the barometric damper for coal use maintains a steady draft automatically, so it will keep going with a steady air flow up through coal as the weather and atmospheric pressure changes. They didn't have the more accurate barometric damper when that stove was built.

We don't have the specifics of your chimney, so we can only assume it is the same diameter as stove outlet, and hopefully has an insulated liner. Without the right chimney it's not going to heat your house efficiently no matter what you do.
** Also depending on your liner, (if metal) you may or may not be able to use coal, since it must have a more corrosive resistant liner to burn coal. **
For a modern stove you will also need the correct size and type chimney to make it work, we can't advise what to use or what you should get without knowing what your chimney is. The cost of a proper liner is more than the stove. You need a stove to match the chimney, or line the chimney to match the stove.
 
In this thread, people say that their coal beds seem to burn between 1000-2000 degrees F: https://coalpail.com/coal-forum/viewtopic.php?f=67&t=488

Why would a wood fire burning cooler than that be dangerous to the stove?
The coal bed also has LOTS of air coming up through the grate to keep it cool. Other wise the grates warp and melt. Coal uses tons of air compared to wood.

Coal heats the rest of the stove more evenly. It is a glowing mass, with small blue flames on top. Wood has very hot and cool cycles. The flame tips are all the way up to the top. (and out the stack) When starting with wood, your stack temp will be 300 -400 like a wood stove. Coal drops stack temp to 100 - 150. (these are surface temps, flue gas is about twice the surface temp) The stove will radiate about the same temp. Just much more even, steady heat with coal.
 
coaly i love reading your posts. i learn quite a bit each time.
thanks
frank
 
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coaly i love reading your posts. i learn quite a bit each time.
thanks
frank
Thanks, I try to explain how things work as simple as possible so people know WHY they need to do what is necessary, not just remember what to do. Something out of the ordinary is always going to happen, so if you know the basics and physics of what makes something work, you can operate it or know what to do to fix it.

It's easy in this case to suggest burning the correct fuel the stove was made for, but if they have an 8 X 8 common masonry chimney, two stories high, that small stove will never heat the chimney area to create enough draft to make the stove work properly AND create enough heat to radiate off it to heat the area they are trying to heat. Back when that stove was used, 3 of them could be heating the same chimney! You had to keep any cold stoves closed tight, but once more than one was going, you had some major draft to help get another going, then back them all off with so much draft. Many people have contacted me with big chimneys claiming they have great draft, but are connecting a small stove that won't seem to heat the indoor area they have. They don't realize a bigger chimney needs a bigger stove with lots of heat loss to have enough to radiate into the home. So they can get a larger stove and go through tons of fuel, or make the chimney right and magically their small stove works great!
 
I installed the stove using single wall pipe to the ceiling box, then insulated 6” pipe through the attic and out the roof, maintaining 2” clearance from all combustibles. There is no masonry involved.

I visited TractorSupply today and they said they have no coal available and no idea if and when they’ll have it back in stock. They don’t offer it for order either, so I guess there is no coal for me.
 
You will certainly need a pipe damper to slow the draft having the proper size and insulated pipe.
Use a magnetic thermometer on the single wall pipe. That will read about 1/2 of actual flue gas temp. The object is to keep the chimney flue temp above 250* to the top. This is only when smoke is present. Over that is wasting fuel up the chimney. Below that allows water vapor from combustion to condense on flue walls which allows smoke particles to stick. This is creosote.

Just as well they don’t have coal. Expect to replace stainless chimney parts every few years burning coal. The top cap rots right off in a couple years. That is the price burning the cheapest fuel. It is even corrosive to masonry over time. They consider Class A “all fuel” chimney, but it doesn’t have the corrosion resistance of liners made for coal, or the cost.

I’d try the pipe damper about half closed once up to temp. You’ll find stove temps moderated and much more controllable. Fires will last longer, but still be short. A wood stove will carry a fire overnight. You burn on an inch of ash and it slows the fire so you have a pile of coals in the morning. You won’t do that burning on a coal grate.

Newer EPA stoves burn smoke at the top compared to burning wood with flames, completely different than older cheap stoves. But you can’t burn anything partially seasoned. Only premium fuel for them. You have the right chimney for a new or older stove.
 
You will certainly need a pipe damper to slow the draft having the proper size and insulated pipe.
Use a magnetic thermometer on the single wall pipe. That will read about 1/2 of actual flue gas temp. The object is to keep the chimney flue temp above 250* to the top. This is only when smoke is present. Over that is wasting fuel up the chimney. Below that allows water vapor from combustion to condense on flue walls which allows smoke particles to stick. This is creosote.

Just as well they don’t have coal. Expect to replace stainless chimney parts every few years burning coal. The top cap rots right off in a couple years. That is the price burning the cheapest fuel. It is even corrosive to masonry over time. They consider Class A “all fuel” chimney, but it doesn’t have the corrosion resistance of liners made for coal, or the cost.

I’d try the pipe damper about half closed once up to temp. You’ll find stove temps moderated and much more controllable. Fires will last longer, but still be short. A wood stove will carry a fire overnight. You burn on an inch of ash and it slows the fire so you have a pile of coals in the morning. You won’t do that burning on a coal grate.

Newer EPA stoves burn smoke at the top compared to burning wood with flames, completely different than older cheap stoves. But you can’t burn anything partially seasoned. Only premium fuel for them. You have the right chimney for a new or older stove.
There are plenty of class a chimney systems that are coal grade