COAL USE IN HOT BLAST 1557M

Well this should go to the boiler room. Anyhow what kind of coal are you trying to burn? If its anthracite, then good luck. I have had nothing but bad luck for these furnaces aren't made for anthracite. If its the soft ohio coal then you should be okay. You should only have air coming from under the grates when burning the coal. So on your door I would shut the damper. Hope this helps.

Moved to the boiler room in hopes that someone there can help... Other than seconding the "air should come from the bottom" comment, I'm not able to suggest anything else - sorry...

Gooserider

I never use coal in my furnace, which is more or less a larger version of yours. I tried, since I heated with coal before, and happened to have a few bags laying here. Made more of a mess than anything. Had to wait for the hot, but still not burning coal to cool enough to get it into a bucket and take it outside. My furnace has a manual draft, and had a fairly poor draft before the reline. Couldn't get that stuff to burn properly. And I grew up with a huge coal boiler in my dad's business that I had to take care of on Saturdays. I think without a really strong draft (overdraft for wood) or a forced air draft, coal is really impractical to burn on a regular basis in these units. I suppose it would burn if I really kept at it and learned, but I'm still back to the "why pay someone else to dig my heat out of the ground?". If I wanted to heat with coal again, I'd make sure to get a stoker- the one I had before really threw some heat. I'm burning PA Anthracite by the way.

a col fire MUST have underneath air to survuive, be advised though , that over the top air can cause an overfire when added, cut the air under to whats needed to hold the burn , but close the top air way down first then balance the air underneath

If you have any sort of decent draft in your flue burn Antracite. It's a lot cleaner burning than Bituminus. It's already been said that The airflow must go up through the fire, but use the draft controls on the upper and lower doors to regulate the fire. Using only the lower draft and having the upper one closed is a good way to over fire the appliance. Combustable gasses can accumulate at the top of the fire box when burning coal. If you keep the upper draft control closed while burning a coal fire you can ignite these gasses when you open the door to stoke the fire. The result will be a rather dramatic blue flame singing your eyebrows. I've been burning anthracite for six years and love it. Be patient, you'll get the hang of it.

Not every furnace that is rated for coal can burn anthracite. The firebox should me flat on the sides, with the whole bottom as shakergrates. The Hotblast has a tapered box which if not modified is a poor choice for anthracite. Call usstove and they won't be able to help you with anthracite. Its built for bit coal.