Not a Lot of Heat

Well for the second time I am trying to burn some good anthracite coal...the first time I was burning nut coal and it would not stay burning...The manufacture said my fire chief furnace with shaker grates would burn stove coal which is bigger...I can get it to burn with nice blue flames...But not a lot of heat...temps this weekend was 26 on an average and the house was only 69 degrees with everything opened up on the bottom ash door below the fuel...when I close it down a little and use the manual damper it would reduce the output. I have tried all sorts of diff things..I have read that the v bottom furnaces do not burn coal good due to the configuration..Can anybody help or suggest a few things?? thanx in advance Redcoals

Hi redcoals,

I believe that my Clayton is very similar in design as your Fire Chief. Here is a link to a post that may help. Slow Blue Dancing With Red Dressed Ladies in a Clayton I looked at the Fire Chief before I bought the Clayton. The fire Chief looks like a very well built unit, but just like the Clayton, Energy King, Woodchuck, and Brunco, I have found that they perform best with the most heat fired on wood. Bit coal comes in a close second with a ton of ash and a lot of soot, with twice the burn time as wood. As for anthracite, I have found that for some reason these kind of furnaces only produce about half the heat output when fired on anthracite. It doesn't matter what size of anthracite either, I've tried them all. It is the burn times and the complete combustion staying under the ash fusion temperature of the coal that I've found in the different sizes of the anthracite.

Here is a neat calculation I found to give you the estimated amount of potential BTU's of a coal stove or furnace.

Grate Area in sq.ft. X .65 X 8 X 12,500 = BTU

For example:

My Clayton 1600 grate is 24" deep X 8" wide = 192 sq.in. or 1.34 sq.ft. X .65, the % of efficiency of the stove X 8, the number of lbs. of anthracite per sq.ft. of grate X 12,500, the BTU's average of anthracite = 87,100 Btu's.

Well that is a lot lower that the advertised 140,000 BTU output.

Well, change the values for wood, 20 lbs per sq.ft. of grate area and 8,000 BTU's for wood and guess what? 1.34 X .65 X 20 X 8,000 = 139,360 BTU's Close enough to the advertised Btu.

So, if you have the blue ladies dancing and have continuous good burning results, you may just be at the sweet spot for the design of your stove and nothing you do is going to pump out more heat. That is what I've found out from burning in my Clayton. Pushing it hard only results in clinkers and short burn times. Burning it in the sweet spot is happy and continuous.

I hope I helped. DOUG

Doug...I have read that post before..Thanx, I think you have hit this right on the head...these furnaces are beautiful wood burners and produce tons of heat burning wood.
I have read before that the furnaces that have this V shaped fire box do not burn coal very good, the coal that lays along the fire brick never burns and then you have to stir and that is not good....So anyway wood it is..Thanx Doug....But still anyone else have an ideas? Redcoals

Red coals:
Even though you thought you bought good anthracite you might have bought a lot of rock. I'd go to a breaker or different coal dealer with some buckets and buy some other coal. You might have bought too hard of coal. Super hard anthracite won't burn. You might try a softer coal. I've had coal that glowed nice and red in the box but no heat. I finally dropped my whole fire and built a new one. Had that happen 2xs. It was just some bad coal.
I had one of those....sold it. The grates were terrible. The configuration is more for wood than coal. You might not be able to get enough draft for coal.

I'd look for a red ash nut or stove, red ash catches much easier than the white ash, and it is more forgiving.