I am currently using a Harman Mark III coal stove. I feed it nut coal. I usually burn three tons of coal for the year. It heats my 2000 square foot home without a problem. I have to carry the coal from the basement and it's kicking my butt carrying it upstairs. At 63 years old my body doesn't like it. I was thinking of getting a pellet stove to replace the coal stove. Any suggestions for the pellet stove? The Harman stove can put out a lot of heat which is hard to regulate the heat. You can only turn the coal stove up so far before you use lose the fire. The stove has a top 6 inch exhaust pipe and would need the same on a pellet stove. I appreciate every ones help.