Yukon Multi Fuel Furnaces

Has anyone had experience with any of these? Iam considering the Super Jack add on wood/coal,planning on burning mostly anthracite coal i see it has cast iron grate but it is not a shaker grate,will it stand the heat from the coal? any ideas as to what size coal would work best? Also about what square footage will it heat in a well insulated house? Iam presently heating with a Fawcett 85000 btu wood/coal add on,doing a great job,been there since about 1985.Any suggestions are appreciated. Regards mills4135

in the top right corner use the search button and type"yukon multi fuel furnace". Member "Dennis H" has one and is very happy with it

Don't buy anything without a shaker grate. Do buy something designed from the ground up for coal and you can still burn wood in the milder weather. A coal burner has rocking grates and a compact brick lined fire box with vertical sides or very near vertical. That compact fire box means shorter wood but will burn coal properly. Most that you will look at will be badly designed.

Thank you Dennis and Franco b,anyone got any particular recommendations,preferably coal/wood and Canadian C.S.A.certified as i live just across the Maine border in Canada? Regards mills4135

The problem with coal/wood is that in order to meet current regulations for wood require in general a more sophisticated system of heated secondary air to burn the smoke. This complicates the stove and does nothing for coal burning. It still will not burn clean unless run fairly hot. To burn either fuel well the appliance has to be designed for it and it alone.

To burn wood in a coal stove can still be pretty clean but only if you settle for a hotter fire and shorter tending times as you probably realize with your present setup. Coal requires bigger ash pans than wood as well. So many have under size pans. Wood is about 2 percent ash while coal is 10 percent or more. A thermostat on the stove also is very convenient to adjust the air automatically because coal responds slowly to a fresh charge and several hours later when fully ignited can be putting out more heat than you want. The thermostat compensates for this and is very easy to adjust for just a tad more heat or less.

I don't know what they have as add ons but you can check the offerings from Hitzer and DS Machine who both have received good ratings from users on this forum. You could also consider a stoker but that would leave out wood burning.

A word on furnaces. Some are just a big sheet metal box with a fire in the middle. Unless those hot gasses are forced to make close contact with the sheet metal, heat exchange will not be very good.

Thanks franco b,i looked but they were mostly stoves,i was really trying to find a furnace for the basement and not have to jerryrig duct work and plenums etc.I have been looking at the Neumac furnaces but the heat exchanger is only 14 gauge where as the add on Yukon has a 7 gauge exchanger but no shaker grate so what do you do?

The best antique stoves had sheet metal of about 22 gauge and many have lasted over 100 years.

I would not forego the shaker grate. The lighter gauge steel, and 14 gauge is not light, (about like most fuel oil tanks) will conduct heat better. Protect it in the off season with WD40 or something better, and it will last forever.

The fire will go out without clearing the ash and lead to constant frustration with poking from above and below to get rid of the ash. You will also be stirring up a lot of fly ash much of it in your face and everywhere else. A furnace maker that claims a model to be a coal burner without proper grates is just flat out lying no matter how well built. When laying out thousands for a unit you should get proper design and not have to go through all sorts of makeshift contortions to make it work. Any shaker or rocking grates also have to be robust. Most of what you see today are toys compared to the old boilers and furnaces.

A good coal burner starts with the combination of fire box and grate. Along with that is an adequate size ash pit and pan. After that comes the heat exchange. No matter what you look at there will be shortcomings because most makers do not understand coal burning, or wood either for that matter. For the most part their background is in fabricating metal. What you are looking for is the least bad in a bad lot.

Just a quick correction,i went back to the Yukon site and reread the specs and it is the fire box.on the Big Jack furnace that is 7 gauge, Not the heat exchanger as i had incorrectly posted previously ,must have been having one of those senior moments.Once again thanks franco b,i now understand as with most things in life one must be prepared for compromise in the pursuit of the non -existent perfect coal/wood furnace.

IMO, I think the Yukon furnaces your looking at are more a wood burner than coal. look at the Newmac add on furnace/GAO model, it's specificly made for coal and will burn wood also and is made in canada http://newmacfurnaces.com/index.php?opt ... Itemid=380

The Newmac looks like they took their wood furnace and added grates and a door underneath. The fire box does have vertical sides but is too narrow, ideal is round and next square or close to it. There is no designed heat exchange, just a baffle to help direct flue gas. Unless cast iron and heavy it will warp or burn out with coal.

I would keep looking. The problem with coal is there is not enough demand to justify a unit designed from the ground up for coal assuming they are even able to. So they add grates to their wood furnace and call it a coal furnace. It will probably work but be far from ideal.

franco b wrote:The Newmac looks like they took their wood furnace and added grates and a door underneath. The fire box does have vertical sides but is too narrow, ideal is round and next square or close to it. There is no designed heat exchange, just a baffle to help direct flue gas. Unless cast iron and heavy it will warp or burn out with coal.

I would keep looking. The problem with coal is there is not enough demand to justify a unit designed from the ground up for coal assuming they are even able to. So they add grates to their wood furnace and call it a coal furnace. It will probably work but be far from ideal.

good to know and still learning everyday

franco b,do you mind saying what you run for coal burning,approx cost and availability? I will take no offence if you would rather not.once again i want to thank everyone for their input up to this point,at least i have not wasted a bunch of cash on something that will not do the job.Regards mills4135

mills4135 wrote:franco b,do you mind saying what you run for coal burning,approx cost and availability? I will take no offence if you would rather not.once again i want to thank everyone for their input up to this point,at least i have not wasted a bunch of cash on something that will not do the job.Regards mills4135

I have a high ranch(built 1990 and fairly tight with good insulation) with finished lower level. The house has oil fired baseboard heat. On that lower level I have run a number of stoves, right now a Glenwood Modern Oak 114 antique. Upstairs I run a mid size Franco Belge. Because I am an enthusiast and want to try different stoves this precludes any permanent installation such as you have in mind. Yours will be better because it will distribute the heat better. I have always been able to sell the stoves I am through with for a profit which more than pays for the next stove. So my aims are different than yours. My background was in oil burners and my interest was always in achieving good clean combustion. Not an easy thing top do with oil burners built in the 1930s and 40s.

To burn any fuel in the best way possible means mixing the air as evenly as possible and maintaining adequate heat where the fuel is burning. With coal the problems are also to keep the entire bed free of ash to allow air to mix thoroughly. A round fire pot does this best along with a grate design that facilitates clearing the ash. When portions of the coal bed are deprived of air carbon monoxide is formed. It's not just that this is poisonous but that it can be burned as well. Not burning it just wastes fuel. The round fire pot will generate less and if insulated with fire brick will burn more of it. Square and rectangular fire boxes certainly can burn coal but always have ash build up in the corners.

If I were to buy something like you have in mind I would seriously consider a stoker but one of the triburner type which burns the coal on a flat plate and just pushes the ashes over the edge to the ash pan. They do tend to deposit more fly ash in smoke pipe and other areas though. Also you can't burn wood if that is important.

This really does not answer the question of what to buy. Unfortunately I don't think there is a lot to choose from as there is in buying an oil or gas fired boiler. Whatever you can find will probably have compromises because the market for forced hot air hand fired coal burners is so thin. Even for plain hand fired stoves there are only a few makers that have had good revues. I would consider a thermostat to control the air a must though.

I'm understanding that more as i continue this quest,as you say the more i look the more i see you would need the features of several different models and brands to have all you would need for a really excellent single multi fuel unit.Having said that,does anyone have any thoughts or experience with the Harman SF-2500-A wood/coal furnace? Thanks once again franco b for pointing me in the right direction as to what is to be avoided and what is absolutely necessary to have if a multi fuel is to be even moderately acceptable in performance and life span. Regards Mills4135

Curious...you are "just over the ME border" where? Top of the state? Like Fort Kent area?

What is the cost for Coal, Oil, And Wood up your way??