Welcome to the Forum my fellow SF-250 owner.
I am late to the post as i tend to jump on here as the season gets closer to the burn season. Just ordered my coal and am getting ready for winter.
"Winter is coming". ( I love that the Game of Thrones has made it such a pop culture saying).
I am a bit more low tech than the people here. I still use a manual damper as that is what I am most comfortable with and do not like having any openings in my stove pipe. I want all the gas to exit up the chimney and do not want any openings to allow any potential leakage. If that means a bit stronger draft during windy days. then so be it. I err on the side of a strong draft. Coal likes air.
Search the forum for posts on how to shrink the firebox using a plate of steel and firebrick. I do this to shut down 2/5th of the firebox. Only three of my grates are used (back ones). When the real cold hits, you can remove the firebrick and crank up all 5 grates and use the full capacity of the stove. You will save on coal in the fall and spring. You may also find that where you live, you may be fine with only using the 3 grates all year long.
As people mentioned, coal likes a deep bed. By shrinking your firebox you can increase the depth of the coal pile and not have to try to spread out a thin layer of coal to keep from being blown out of your house with all the heat. lol.
Feel free to ask any question you have. I am more than happy to give you my opinion. Hehehehe.