Wood verses coal

[humbug]

I recently purchased a wood stove that will burn coal also.
I am gone from home when I work about 15 hours a day. I know that no wood stove will last that long on a load of wood and I will need to use an alternative form of heating on the days that I work.
I don't know anything about burning coal. Will it last longer than a load of wood? How much longer? Is there anything special that I should do when burning coal that you don't do while burning wood?
Any info on coal burning would be very much appreciated.

Hum

[CarolAnn]

I don't believe coal will last as long as wood. When I had an airtight wood stove, I'd load it with very dry wood to get a blazing hot fire going quickly, then add large pieces of green wood and shut it down tight. The heat dried out the green logs and they held the coals for quite a long while; at least overnight. Open the damper screws the next morning and it would whoosh into hot flame. But 14 hours? I'm not sure I ever got it to hold that long.

It also took some practice to get it just right. Turn it off too soon and the fire just went out. Too late, and the green wood would be so hot, it'd just burn out. I found hickory was very good to hold coals, but it was also good at making tiny fire bombs that would jump out and burn holes in my clothes! Several good large pieces of green (wet) oak of any species will hold it's coals well too, if put in a very hot starter fire.

Here are some links for coal tips that might help you.
http://hearth.com/econtent/index.php/articles/coaltips

http://www.homewarmth.com/pdffiles/coalburningtips.pdf

I guess that since coal is in smaller chunks than a log, it wouldn't hold the heat so long, but it may burn hotter.

[kawalekm]

Hello Humbug
I researched a bit when I picked up a used stove that's both wood/coal. Apparently, you must use a grate to hold the coal off the bottom of the stove, to allow air to get to the coal from the bottom up which does not burn as well if the air is admitted sideways, as with a wood only stove. Secondly, coal burns "hotter" than wood and the grate keeps the coal from burning out the bottom of the stove. You need to line the bottom of the stove with firebrick or a layer of sand. Look at the photo of this stove.

http://i141.photobucket.com/albums/r55/kawalekm/Federalwoodstove.jpg

The two round disks on the front of the stove are the air control vents. the top one is for wood, while the bottom one is for coal. You rotate them CW or CCW to regulate the amount of air getting in. The depth of the bottom door (about 4 inches) gives you a sense of how much elevation the coal grate needs. It also functions as the ash removal door. Did you get any kind of instruction manual with the stove?

The big question though is there a coal supplier anywhere nearby? Are you in an area that has beds where you can harvest your own coal? Our property is Oak woodland, and I plan on supplying 100% of our wood from our own homestead. Yes, 15 hours is a long time. What's the biggest chuck of wood that can be stuffed into the stove at one time. That might work for you.
Good luck,
Michael

[Darrel]

My chief source of heat is wood and coal. Pound per pound coal burns longer and hotter. The downside to coal is it burns dirty and if not careful can leave your house a little dusty.
I use a Wondercoal wood and coal burner. It has a lot of chamber space and a option for a blower to circulate the heat. I can load the chamber completely with oak, hickory, or beech and it has burned for up to 12 hours with the drafts turned all the way down. I will if need be place a few lumps of coal on the wood to extend the burn time.

[kawalekm]

Hello Hum
I think I answered this somewhere else, but I think a small kerosene heater might fit your requirements. This last winter I picked up a Corona DK21 kerosene heater at the flea market for 25$. It was almost new, but not working untill I swapped out a new wick. After that, it worked beautifully, with a blue flame and no smoke. What I found was that if you set it at a medium setting, you could light it at about 6pm and it would still be burning the following morning at about 6am.

What I image you can do, is light the kerosene stove on mornings when you plan to be gone all day, and start the woodstove at times when you know you'll be home to tend the fire.
Michael

[woodburner]

Hi all,
Heat my house with a Vermont castings resolute wood and a Vermont castings vigilant coal. As far as burn time I can get 6-8 hours wood but then need to work the coals to restart the fire but with coal i use a mix of nut and pea and can 10-16 hours. I love the wood fire - it looks great, is fun to cut, chop, and split but the coal burn time and heat output is incredible. I don't think a wood fire gets hotter than 800-1200 degrees even in a post combustion chamber but coal can reach 2000 degrees - great for those long cold nights in January.

In NE PA Anthracite is available for $160.00 a ton or less and that is equiv. to 1+ cord of good hardwood or 250 gallons (ugh) of oil. The only way wood is cheaper is when I cut it myself. Only drawback to coal is it gets too hot at times and the ashes need to be disposed of (they will kill plants with their high sulfer content).
Both have their place but as long as your stove and chimney are setup for both -


Remember: NEVER burn coal in a wood only stove or in a stove venting into a metal chimney not designed for coal!!
l

[MadTripper]

I think the biggest variable in your situation is the type of wood you use. *I also live in NePa and we have a nice supply of hardwoods available. *In my last home, I had a Kodiak double door that I could keep going for 14 hours. *The heat obviously wasn't cranking like if I was home however it kept the thermostat above 70 which was where my baseboard was set to turn on.

The importance of properly seasoned wood can't be stressed enough. *I have used green woods in my stove but typically, the results aren't favorable. *The only wood that I have had luck with burning green, is ash.

The longest burning types I have found are Beech, Hickory, and Locust. *Locust gets a bad rap but overall, it is one of the hardest woods in the world. *It pops and throws sparks but in a contained stove, who cares!?

When I know I'm going to be gone for a while and there isn't anyone at home to tend to the stove, this is how I tackle stove duty:
As soon as I'm up, I open the vents all the way and put some dry, small wood in the stove.
I let it blaze while I take care of showering and getting ready.
About 15 to 20 minutes before I leave, I load the stove with large blocks of Beech perferably.
Shut the dampers down all the way and then open 1/4 to 1 full turn depending on your stove.

I could consistantly get 12-14 hours out of my stove and even had one day I got 24 hours. *Now don't get me wrong, it was about as dead as it could get but I was able to throw some kindlin in and it started back up.

This is a pretty good link listing common wood types and their quality's when it comes to burning.

http://mb-soft.com/juca/print/firewood.html

I haven't used coal but the stove at my new home is a beautiful masterpiece created by a local guy quite a few years ago and can handle it. *The whole bottom half is firebricked, it has a forced air draft, a draft on the bottom, two drafts on the door, and a forced air chamber which forms the throat and throws the hot air any direction I feel like ducting. *The only thing I'd like to do is add some form of outside air intake to it. *I installed a radiant heating system so hopefully, I won't need to use a ton of wood this winter. *Here is a photo of the stove in case you are interested.

http://www.madtripper.com/gallery/v/Various/houseconst/cabinets_stove/aug06+030.jpg.html

Tripper

[Westcliffe01]

Humbug *It is highly recommended to purchase a modern stove and not one of the ancient "pre 96" smoke dragons. * All stoves that are EPA certified will burn clean and that way save you a lot of money on the real expense item: FUEL

Harman makes a line of coal stoves that I have seen in action and they work really well:
http://www.harmanstoves.com/list.asp?id=13,14,15,16,17&title=Harman%20Hand%20F ired%20Coal%20Stoves

Even the smallest one will burn for a claimed 24 hours on a load of coal. *No-one has found a way to get a stove to pass the EPA certification when burning either coal or wood, so all new stoves are purpose built for the type of fuel.

I didn't find the smaller Harman expensive either, it was a lot less than a lot of cast iron woodstoves.

[woodburner]

Certainly agree with the choices of wood above - beech, hickory, and locust - but hickory and locust will dull chainsaw blades quickly. Keep the blades sharp and keep spares. I always have three blades with me at all times. And the emphasis on seasoning the wood cannot be stressed more.
But I do take exception with the 'wood dragon' comment, it depends upon the stove. Many people do not burn their stove hot enough or use dry enough wood so they are sending a lot of particles or water up the chimney.
My wood burner is a pre-1989 VC Resolute - which has a large firebox, easy loading , downdraft function and is still going after 5 cords per year - I have a c. 1830 farmhouse with solid brick walls and no insulation in them and burn that stove hard. It is probable the best resolute model ever made but now I am fabricating my own parts since many items are out of production.
But the day will come when I have to take it to the scrap yard and then I'll have to settle for a new stove.
WB

[MadTripper]

I agree with woodburner. I know there are some newer units available with catalytic converters and so forth however I think the wood is the key. Seasoned hardwood burns well and provides the most heat with very little creosote buildup. Controlling the air intake is also important. The gaskets and pipes should be checked regularly.

There is a ton of info on seasoning firewood. This link has a great method that works quickly and doesn't require a storage space for it.

http://www.thechimneysweep.ca/6seasoningwood.html

Tripper

[JakeLeg]

I'm also in NorthEast PA - the coal capital of the Eastern, Northern quadrant Pennsylvania!

A buddy just put in a coal/ wood stove that looks a heck of a lot like those Harman models. Although he plans on burning coal. He claims he can get stove coal for 120 a ton.

Wife and I currently have oil supplemented by propane. I had planned on putting in a wood stove for this winter, in the basement. Our house was built with a coal stove as is evident from the gravity vents that go from the basement to the first floor and the first to the second.

I'm glad i decided to hold off on that project for this year since I saw my friend's setup. I'll most likely do something just like his for next winter (price out the chimney work next spring or summer).

Question for the coal people: what kind of VOLUME does a ton of stove coal take up? Logistically, I will have to locate the stove in a different location than the former one. Likewise, i will have to store the coal in a different location. I'll have to make up new bins, and will need to size accordingly.

[woodburner]

I have two coal bins made out of old skids about 42X42 inches. I used oak skids (poplar will rot) and put plywood up the sides using the skid as a frame for the bottom. The sides are 36 inches high and there is a hinged lid. I reinforced the corners and top edges and can get about 1000 pounds in each. I buy my coal in bulk they just dump it in my pickup. I put a tarp in the bed just before they dump the coal so it is easier to clean out when done. Smaller coal packs better so it will take less room. I also have 6 5 gallon buckets for overage and also use them to transport to the house. I'll try to post pictures one of these days.
wb

[humbug]

I envy you guys your hardwoods. The woods I have available to me are mostly softwoods. we have cottonwoods, quakies and pine mostly. The only hardwood we have available in abundance is juniper. I plan on using this at night and when I am gone. The softwoods will be used when someone is available to refill the stove. We can occasionally get mahogany here but have been told it is not recommended to burn in a wood stove. Any ideas why?

[woodburner]

I don't know why mahogany would be bad unless it has to do with the oils in the wood. If it is oil then I would imagine either the oil would create creosote (more of a sugary oil) or if the oil was dense enough then the wood may burn too hot for a standard wood device. But, it is an interesting question though. If mahogany is an issue then what about teak - but who would burn such an expensive wood.
I don't burn much soft wood (gopher wood) but find that the oily pines do better when they are very dry, then they seem to make less creosote but that may be just because the fire burns hotter with dry wood then wet wood.
wb

[Gibbonboy]

Not sure why mahogany would be a problem, unless it's cut small and very dry, which could cause an overfire.

No stove is "EPA Certified" for wood and coal. Most are exempt "35 to 1" devices, also central heating appliances are exempt, although there are several who meet the particulate threshold from EPA, and one of them will be my next purchase. Several manufacturers claim their stoves as "EPA Certified" when they are in fact certified to be exempt. Also, without an actual UL or WH plate and cert. number on the stove, it should not be installed in a residence.

My wood furnace is in the basement, but due to heat loss, a regular stove should NEVER be put in an uninsulated masonry basement. I heated with coal for years via a stoker in the basement, and could never figure out why my heat just "disappeared". With my furnace heating only the air in the living space above, the house is very much warmer. I also installed a SS flex chimney liner, as an outside masonry chimney is a no-no as well. My draft is massively improved, and my stove burns much cleaner now.

You really, really should never burn coal in a wood-only stove, and never in one with a catalytic combustor. Putting ash or sand on the floor of the firebox is a stopgap solution at best, and not for regular use. I stopped burning coal because of the cost, and because the stove produces massive amounts (compared to wood) of ash and cinders. Also, if you do not have sufficient draft, you stand a very good chance of killing yourself with coal. My current furnace will burn coal, and I have done so, but I haven't bought coal in 2 years, and don't ever plan to again. Wood is so much more pleasant to deal with.

Enough of my ranting, but I've seen some SCARY installations of stoves, complete with owners who think they're doing fine. If you've been doing something the wrong way, it doesn't matter how long you've been doing it, it's still dangerous to you and your family. Best of luck.