All of the Front Loading Boilers (except for the Eco-FLRH-85) are coal burning boilers to meet the Federal EPA guidelines.
The Federal Government copied the laws in PA where coal is abundant and they would never outlaw coal for heating a residence.
This makes it legal to sell the coal version to anyone in 49 states. This boiler will burn coal but will also burn wood even better than normal because of the forced air induction blower that blows oxygen in from the bottom, up through the grates, just like a blacksmith's forge.
See the HyproTherm Boiler Prices Page for current pricing on a boiler that will burn wood or coal.
Remember that you can also buy a water-less furnace model that is legal for heating a residence in 49 states because it is not a boiler and most laws talk about OWBs, which refers to outdoor wood boilers. Obviously, a water-less furnace is not a boiler.
Outdoor Coal Burning Boiler Prices