Can I convert Hardy H5 wood boiler to coal

[Hightop830]

Brand new to site plus new to possible coal burning. Currently 73 years old. Been cutting and splitting 12 cord a year for heat in Minnesota. Getting too old for that! Currently have Hardy H5 boiler. Been reading on your site and understand I should place fire brick inside box to act as heat sump. Underneath fire box is ash tray which inside measures approximately 12" x 36" x 36". Temp on demand fan blows into this area to stoke wood above. Are there any suggestions to form a shaker below grate which wood sits on top or would I need one? Grate below wood has openings approximately 1" x 4" so wood ash fall by gravity? I plan on using lump coal as I can get out of ND for 145.00 per ton. Lastly any ideas on how long a ton would last? Currently with wood at minus 25 I stoke 3 times in 24 hour period. Thanks in advance

[warminmn]

Ive burned that coal from that dealer. You'd want the lump size you mention, not the stoker size. Whether it would work in your stove or not Im really not sure. Would need some pictures or if you could find the manual online that might work.

It might be a case of burning wood and the lignite together. Light on the wood but it may be neccessary. I'd just get a pickup load and try it, mixing with wood first and then keep using less wood. That would give you some experience. Your going to need air from underneath it, thru the grate to burn it. Unsure about using any fan blowing on it, not my expertise with that.

Im going to take a wild guess and say 25 ton to replace 12 cords of wood. It could easily be more. I doubt much less. I kinda had it figured out that 2 to 2.5 tons of it got me the same heat as 1 ton of anthracite. 1 ton of anthracite is supposed to be the same as a cord of wood but it never worked that way for me. But if that were the case it would be about 30 tons needed. i was burning it in my house with a hand fed stove. I had zero trouble with creosote buildup from it in my pipes, your results may vary. It makes some smoke at first then burns cleaner. Smells like tires burning.

The seller may give you a deal on a semi load but try it before doing that. It needs to be stored indoors or well covered as it kind of comes apart with time from exposure to the elements. Brown dirt some people call lignite.

[Richard S.]

Lastly any ideas on how long a ton would last? Currently with wood at minus 25 I stoke 3 times in 24 hour period. Thanks in advance

A cord of wood(8*4*4) is roughly about 22 million BTU's assuming seasoned hardwood. If it's soft wood it might only be 17 million. If it not seasoned it's lower for both. Anthracite has about 24 to 25 million BTU's per ton and you can fit 3 tons in the same space as one cord of wood.

The internet is telling me ND coal is lignite and 10 to 20 million per ton so that's a pretty big variance. Even at ten million it should have more energy density than seasoned hardwood assuming lignite has same volume of anthracite per ton.

[warminmn]

I think it is 13-14 Million with that lignite mine when I looked into it 3 years ago. I was likely wasting some of the heat getting it burning good before closing it up, something I dont have to do as much of with anthracite, if at all. So he might get better results than I did on that part. I still think it would take 25 tons or close. Doing the math says less than Im guessing.