That Saey likes Pea coal. My buddy has one. Very quirky to run, but you'll get the hang of it. It likes to roast you out of the house, so burning nut would put you in Chernobyl territory.
The spring loaded air flapper in the back is VERY sensitive to adjustment. Trial & error will get you in the ballpark eventually. You definitely want a solid week of 30's to really have a good test of what it is capable of.
Keep in mind, this could be because he has a strong draft - your chimney will be different, so you may end up with nut after all. You'll have to try both & see what works for you.